EKINSUN LTD is a custom parts manufacturer that machines garden hose thread adapters to drawing: 3/4-11.5 NH male or female on one end and NPT, BSP, metric fine, M22×1.5, hose barb, JIC or tri-clamp on the other, in free-cutting brass CW614N, DZR brass, lead-free brass or 303 / 316L stainless, from 1 piece. A garden hose thread is 3/4-11.5 NH: 11.5 threads per inch, a straight 60° thread with a 26.56–26.99 mm (1.0455–1.0625 in) major diameter on the male end, sealed by a flat washer at the bottom of the female coupling rather than by the thread itself.
An example of where the line falls: a 1/2 NPT chiller drain that needs a garden hose takes the 3/4 MHT × 1/2 FIP brass adapter from any hardware store. The same adapter in 316 stainless, with a 12 mm barb instead of the hose thread, or screwing into an M16×1.5 pump port is machined.
What size is garden hose thread?
Garden hose thread is 3/4-11.5 NH
Garden hose thread (GHT) is the 3/4-11.5 NH thread of ASME B1.20.7: a straight, non-tapered 60° thread with 11.5 threads per inch (2.209 mm pitch) and a major diameter of 1.0455–1.0625 in (26.56–26.99 mm) on the male end. The joint seals on the flat washer inside the female swivel coupling, not on the thread, which is why a hose end never needs tape. One thread size serves every garden hose: 1/2, 5/8 and 3/4 in hoses all carry the 3/4-11.5 NH fitting, and the “3/4” in the name is the nominal hose size, not the thread diameter.
| Feature | Male end (nipple, spigot) | Female end (swivel coupling) |
|---|---|---|
| Major diameter | 26.56–26.99 (1.0455–1.0625) | 27.24 min (1.0725) |
| Pitch diameter | 25.34–25.55 (0.9975–1.0060) | 25.81–26.02 (1.0160–1.0245) |
| Minor diameter | 24.12 max (0.9495) | 24.37–24.80 (0.9595–0.9765) |
| Threads per inch / pitch | 11.5 / 2.209 (0.08696) | 11.5 / 2.209 (0.08696) |
| Thread form | 60°, straight, basic height 1.435 (0.05648) | 60°, straight |
| Seal | the face of the male end | flat washer at the bottom of the coupling |
| Rolled thin-wall form 3/4-11.5 NHR | major 26.29–26.72 (1.0350–1.0520); pitch 25.22–25.65 (0.9930–1.0100) | minor 24.69–25.22 (0.9720–0.9930); pitch 25.81–26.11 (1.0160–1.0280); major 27.13 min (1.0680) |
NH is the full-form thread cut into brass or machined stainless; NHR is the rolled thin-wall form on stamped hose ends. The two mate with each other.
Need garden hose thread (GHT) adapters in a size, thread or material no catalogue lists? EKINSUN is a custom parts manufacturer: we make garden hose thread (GHT) adapters to your drawing, sketch or sample — brass or 304 stainless steel — from 1 piece, quoted in 12 hours and shipped duties paid. If the size is standard, ask anyway — it may be in stock, and the unit price drops as the quantity rises. All custom adapters and fittings →
How to tell GHT from a pipe thread with a ruler
Lay a rule along ten thread crests of the male end: ten pitches of garden hose thread span 22.09 mm (0.870 in), ten pitches of a 1/2 or 3/4 NPT, NPSH or G 3/4 BSP span 18.14 mm (0.714 in), and ten pitches of an M22×1.5 pressure-washer thread span 15.0 mm. Then measure across the crests with a caliper: 26.6–27.0 mm all along the thread is GHT; 26.0 mm at the first thread rising to 26.7 mm at the last is a tapered 3/4 NPT; 26.4 mm is a G 3/4; 22.0 mm is the M22. The diameter alone will not separate GHT from 3/4 NPT or G 3/4 — the thread count will.
GHT vs NPT, NPSH, BSP and M22 — the threads that look like garden hose
Five threads sit within a millimetre of the garden hose diameter and none of them fits it. A 3/4 NPT male starts in a hose coupling and jams after a turn; a hose end forced onto a G 3/4 tap strips the 55° thread; an NPSH pump fitting takes a fire-hose coupling but not a garden hose. The table gives the figure that separates each one.
| Thread | Male diameter mm (in) | TPI / pitch mm | Form | Seals on | Fits a garden hose coupling? |
|---|---|---|---|---|---|
| GHT 3/4-11.5 NH (garden hose, 1/2, 5/8 and 3/4 hoses) | 26.56–26.99 (1.0455–1.0625) | 11.5 / 2.209 | straight 60° | washer in the coupling | yes — it is the hose thread |
| 3/4 NPT (ASME B1.20.1, 3/4 pipe) | 26.67 pipe OD (1.050); about 26.0 at the first thread | 14 / 1.814 | tapered 1:16, 60° | the thread, with tape or sealant | no — starts, then jams |
| 1/2 NPT (1/2 pipe) | 21.34 pipe OD (0.840); 20.7 at the first thread | 14 / 1.814 | tapered 1:16, 60° | the thread | no — 5 mm too small |
| 1 NPT (1 in pipe) | 33.40 (1.315) | 11.5 / 2.209 | tapered 1:16, 60° | the thread | no — same pitch, 6 mm too big |
| 3/4-14 NPSH (straight hose thread on pumps, fire and industrial hose) | 25.94–26.30 (1.0213–1.0353) | 14 / 1.814 | straight 60° | washer | no — 14 TPI; its female takes a 3/4 NPT male |
| 1/2-14 NPSH | 20.59–20.95 (0.8108–0.8248) | 14 / 1.814 | straight 60° | washer | no |
| G 3/4 BSP (ISO 228, UK / EU / AU tap thread) | 26.44 (1.041) | 14 / 1.814 | straight 55° | washer or O-ring on the face | no — 14 TPI, 55° |
| G 1/2 BSP | 20.96 (0.825) | 14 / 1.814 | straight 55° | washer or O-ring | no |
| M22×1.5 (pressure-washer hose, 14 or 15 mm bore) | 22.0 (0.866) | 16.9 / 1.5 | straight 60° | O-ring or cone | no |
| 1 in NH / NST (fire booster and chemical hose) | 34.93 (1.375) | 8 / 3.175 | straight 60° | washer | no — shares the letters NH, nothing else |
NPT and G values from the fitting thread identification chart; NPSH and NH from the ASME B1.20.7 table. Diameters are over the crests of the male thread; NPT figures change along the taper.
Every one of those pairs is an adapter, not a force fit: a body with the hose thread cut on one end and the other thread cut on the other. The fitting thread identification chart reads any of the pipe and port threads by diameter and pitch, and the BSPP vs BSPT note separates the parallel and taper forms of the BSP tap thread.
MHT, FHT, MIP, FIP, NH, NPSH — what the labels mean
Store packaging and catalogue listings name the same thread six ways. The table turns each label into a thread and a gender.
| Label | Reads as | Thread | Example |
|---|---|---|---|
| GHT, GH, NH, NHT, “hose thread” | garden hose thread | 3/4-11.5 NH, ASME B1.20.7 | “3/4 GHT” |
| MHT, MGHT, MH | male hose thread | 3/4-11.5 NH male — the spigot, the hose end, the hose side of an adapter | “3/4 MHT” |
| FHT, FGHT, FH | female hose thread | 3/4-11.5 NH female — the swivel nut on a hose, a fixed female on a Y-valve or timer | “3/4 FHT” |
| NHR | rolled hose thread | 3/4-11.5 NHR, the thin-wall stamped form; mates with NH | on hose-end couplings |
| MIP, MPT, “male pipe” | male iron pipe / male pipe thread | NPT male, tapered | “1/2 MIP” = 1/2 NPT male |
| FIP, FPT, “female pipe” | female iron pipe / female pipe thread | NPT female, tapered | “1/2 FIP” = 1/2 NPT female |
| IPS, IPT | iron pipe size / iron pipe thread | generic for pipe thread; NPT in the US | “3/4 IPS” |
| NPSH, NPS | national pipe straight hose | straight pipe thread with a washer seal; 14 TPI at 3/4, not the garden hose thread | pump discharge, fire and industrial hose |
| NH / NST 1, 1-1/2, 2-1/2 in | national hose / national standard thread | fire hose couplings; the 3/4 and 1 in booster sizes are 8 TPI on a 34.93 mm male | hydrants, booster reels |
| BSP, G, “hose union” | British Standard Pipe parallel | G 3/4 or G 1/2 tap thread, 14 TPI, 55° | UK / EU / AU taps and click-on connectors |
| M22, M22×1.5 | metric fine | M22×1.5 with a 14 or 15 mm bore | pressure-washer guns and hoses |
| 3/4 MHT × 1/2 FIP | male hose thread by female pipe | 3/4-11.5 NH male × 1/2 NPT female | pattern A below |
Three brass 3/4 GHT × NPT adapter patterns — measured
The three bodies below cover most of what a hardware store sells under “garden hose to pipe thread adapter”: a hose thread on one end, a 1/2 or 3/4 NPT on the other, a hex in the middle for a spanner. The figures were measured on the brass parts in the photographs; the drawing is to the same scale.
| Pattern | Ends | Store label | Overall length | Diameters | Mass | Where it goes |
|---|---|---|---|---|---|---|
| A | 3/4 GHT male × 1/2 NPT female | 3/4 MHT × 1/2 FIP | hex body | hex across the middle; GHT 26.6–27.0 over the crests | 48 g | a 1/2 NPT nipple, drain valve, boiler or chiller drain that has to take a hose |
| B | 3/4 GHT male × 1/2 NPT male | 3/4 MHT × 1/2 MIP | 33 mm (1.30 in) | GHT about 26.5 (1.04); NPT 20.7 (0.81) at the first thread | 42 g | a 1/2 NPT female port on a pump, tank, valve or bulkhead |
| C | 3/4 GHT male × 3/4 NPT female | 3/4 MHT × 3/4 FIP | 28 mm (1.10 in) | body 30 (1.18); GHT 26.6–27.0 | 50 g | a 3/4 NPT nipple or valve outlet; the boiler-drain size |
A 3/4 FHT × 1/2 MIP (female swivel to male pipe) and a 3/4 FHT × 3/4 MIP complete the store set; a machined female GHT is a fixed nut with a flat washer seat at the bottom of the thread, not a swivel.
Which end gets tape
The NPT end seals on its taper and takes two or three turns of PTFE tape or a pipe sealant; the GHT end seals on the washer in the hose coupling and takes nothing. A machined adapter with a female GHT end needs that washer seat cut in: a flat bottom below the thread that the male face and its washer land on. Brass on brass gives the cleanest joint; a brass adapter into an aluminium 6061 pump housing takes sealant on the NPT end and a check for galvanic attack in wet service.
What to send for a GHT adapter that is not stocked
- The hose end: male or female GHT; female ends are fixed unless a swivel is asked for.
- The other end: NPT, BSP G, metric fine (M14×1.5 to M27×2), M22×1.5, hose barb (hose inside diameter), JIC or ORFS dash size, tri-clamp ferrule size — with its gender.
- Length over the ends, hex size, and bore if a restrictor or a full-flow bore matters; the three patterns above are 28–33 mm long.
- The water: cold, hot, hard, chlorinated, salt, drinking; or air, coolant, oil — it picks brass, DZR brass, lead-free brass or stainless.
- Quantity: 1 piece is a lathe job; batches of 25–500 are quoted per piece; either way a quote within 12 hours.
Where the hardware-store catalogue stops
| What you need | In the catalogue? | What we make |
|---|---|---|
| 3/4 GHT male × 1/2 or 3/4 NPT, female or male, brass — patterns A, B and C | Yes | Buy it from stock at any hardware store; no one-off competes with a stamped or forged brass adapter on price. Standard parts: ask us too — we may have them in stock. |
| 3/4 GHT female swivel × NPT male, brass, and the double-female or double-male hose menders | Yes | Stock; buy them. Standard parts: ask us too — we may have them in stock. |
| GHT × M22×1.5 for a pressure-washer gun or hose | Yes | Sold as pressure-washer accessory kits; buy the kit unless the bore or the gender is wrong. |
| GHT × G 3/4 or G 1/2 BSP — a US hose on a UK, EU or AU tap or machine, or the reverse | Partly | A few importers list the 3/4 pair; other sizes, female-to-female and stainless are machined, from 1 piece. |
| GHT × metric fine port — M14×1.5, M16×1.5, M18×1.5, M20×1.5, M27×2 on a pump, chiller, cooler, sensor or valve | No | Machined from CW614N brass or 316L bar, each end to its own standard, from 1 piece. |
| GHT × NPT in 303, 304 or 316L stainless, or a length beyond the 28–33 mm store body | No | Machined; stainless for salt water, chemicals and food lines, length to the housing it must clear. |
| GHT × hose barb for a metric hose — 10, 12, 16, 19 or 25 mm bore | Partly | 5/8 and 3/4 in barbs are stock; metric barbs, barb elbows and stainless barbs are machined, profile cut to the hose. |
| GHT × JIC 37°, ORFS, SAE ORB, tri-clamp ferrule or KF flange | No | Machined, the hose thread to ASME B1.20.7 and the other end to its own standard. |
| A GHT adapter with a bore restrictor, a gauge port, a second hex, a bulkhead shoulder with jam nut, or a fixed female with washer seat | No | Machined; drawing or a sketch with the four numbers above. |
| A GHT adapter with a drinking-water approval or a pressure rating printed on it | Partly | Lead-free brass CW724R is machined and the bar certificate follows the batch; approvals and ratings are not claimed for a machined adapter, and we say so before quoting. |
Materials for garden hose thread adapters
| Material | Designation | Where it fits here |
|---|---|---|
| Free-cutting brass | CW614N / C36000 | the adapters in the photographs and the machined ones; cold water, air, coolant |
| DZR brass | CW602N | hot, hard or chlorinated water; costs more, keeps its zinc |
| Lead-free brass | CW724R / C69300 | drinking-water lines where a lead limit applies; certificate per bar |
| Stainless 303 | 1.4305 | free-machining stainless for adapters that need no welding |
| Stainless 304 | 1.4301 / A2 | wash-down, outdoor and food-line adapters |
| Stainless 316L | 1.4404 / A4 | salt water, chemicals, marine deck wash |
| Aluminium 6061 | AlMg1SiCu | the pump or chiller housing a brass adapter screws into; sealant on the NPT end, galvanic check in wet service |
Related pages
- BSP to NPT adapters — the G, R and NPT pairs machined in every size
- fitting thread identification chart — G, R, NPT and metric port threads by diameter and pitch
- Plumbing thread adapters — male-to-female and BSP-to-NPT adapters for pipework
- Hose barb adapters — barbs in brass and stainless for odd hose bores
- Metric to imperial thread adapters — metric fine to G, NPT and UNF
- brass pipe fittings — nipples, bushings, elbows and tees for equipment water lines
- pump fittings — inlet and outlet adapters for pump ports
- Tri-clamp adapters — sanitary ferrule to thread or barb
Frequently asked questions
Garden hose thread is 3/4-11.5 NH (ASME B1.20.7): a straight 60° thread 1-1/16 in (26.99 mm) over the crests of the male end, with 11.5 threads per inch, sealed by the washer in the female coupling. The same fitting is used on 1/2, 5/8 and 3/4 in hoses; the 3/4 is the nominal hose size, not the thread diameter.
No. A 3/4 NPT male is 26.67 mm at the pipe with 14 threads per inch on a 1:16 taper and seals on the thread; garden hose thread is 26.99 mm with 11.5 threads per inch, straight, and seals on a washer. The two start together and jam after a turn. An adapter with 3/4 GHT on one end and 3/4 NPT on the other joins them.
No. 3/4-14 NPSH is a straight thread of 26.30 mm and 14 threads per inch, used on pump discharges and fire or industrial hose; garden hose is 11.5 threads per inch. A female NPSH coupling does screw onto a 3/4 NPT male, which is where the confusion comes from.
Male hose thread by female iron pipe: a 3/4-11.5 NH garden hose male on one end and a 1/2 NPT female on the other, the adapter that puts a hose thread on a 1/2 in pipe, drain valve or chiller drain. MHT and FHT are the hose ends; MIP, FIP, MPT and FPT are the NPT pipe ends.
Only the NPT end. NPT seals on its taper and takes two or three turns of tape or a pipe sealant; the garden hose thread seals on the flat washer inside the hose coupling and takes nothing on the thread.
Yes. 3/4 GHT male or female on one end and a metric fine port such as M16×1.5 or M20×1.5, a G 3/4 BSP, a metric hose barb, a JIC or a tri-clamp on the other, machined from brass, DZR brass, lead-free brass or 303 / 316L stainless bar, from 1 piece, with a quote within 12 hours.
EKINSUN LTD is a custom parts manufacturer that machines garden hose thread (3/4-11.5 NH) adapters to NPT, BSP, metric, barb, JIC and tri-clamp ends in brass and stainless, from 1 piece, with a quote within 12 hours.
No list price. The stock brass 3/4 GHT × 1/2 NPT patterns cost a few dollars and no machined one-off competes with them. A machined adapter is priced by the bar size, the two threads, the material and the quantity: a brass GHT × M16×1.5 is a short lathe job; a 316L GHT × 12 mm barb elbow is a longer one. The quote separates the two.
Send both ends
The hose end (male or female GHT), the other end (NPT, BSP, metric, M22, barb, JIC — size and gender), material (brass, DZR, lead-free, 303 / 316L), length or hex if they matter, quantity. A photo with a ruler across the thread works. From 1 piece, quote within 12 hours.
Not sure which thread you have? Count the threads in one inch — 11.5 is garden hose, 14 is 1/2 or 3/4 pipe — measure across the crests with a caliper, and tell us what the other end screws into. A photo with a ruler across the thread answers most of it.