Selection
How to choose an air hose for a compressor and pneumatic tools
Pressure class, inner diameter, length, oil mist and temperature: what to check when choosing an air hose for a compressor and pneumatic tools.
Storz coupling sizes: DN and lug distance
Why two numbers describe a Storz coupling, which heads connect to each other, which DN fits which lug distance, and how to read our article numbers.
Storz couplings are symmetrical: two identical heads with lugs connect with a quarter turn, and there are no male and female parts. That makes them quick to use, but it also means that a Storz coupling is described by two numbers, not one. Here is how to read them.
Two numbers: lug distance and DN
- Lug distance — the size of the Storz head, set by the distance between its lugs. Two heads connect only if their lug distance is the same.
- DN — the size of the hose tail or thread on the other side, which has to match the hose or the pipe.
The same DN is often available with different lug distances, and the same lug distance with different DN. So a DN 52 hose can end in a head with lug distance 66 mm or 81 mm — and it will connect only to heads of the same lug distance.
Which DN fits which lug distance
For the Storz coupling with ribbed hose tail, made for suction and delivery hoses, our range is:
| Lug distance, mm | DN, mm |
|---|---|
| 31 | 19, 25 |
| 44 | 25 |
| 52 | 38 |
| 66 | 25, 32, 38, 52 |
| 81 | 38, 52, 63, 75 |
| 89 | 63, 70, 75, 80 |
| 115 | 100 |
| 133 | 100, 110, 150 |
Other Storz parts — couplings with barbed or smooth tails, adapters with female or male thread, swivel adapters — have their own size tables on their pages. In fire-fighting equipment the common sizes are also known by letters: D for lug distance 31 mm, C for 66 mm, B for 89 mm and A for 133 mm.
Reading our article numbers
For the Storz coupling with ribbed hose tail, the article number contains both values: 240 052 066 is DN 52 with lug distance 66 mm. Search the site by article number, and you go straight to the right row of the size table.
Seals and accessories
Storz heads seal with DS seals for suction and delivery hose couplings: NBR, white (ID 25–115 mm) or silicone, transparent (ID 50–100 mm). The range also includes a reducer between two Storz sizes, a blank cap with chain, a spanner and a split lever for assembly.
Pressure and temperature
The working pressure and temperature of a Storz coupling depend on its size, material and seal, so we confirm them when you order.
Not sure which size you have?
Send us a photo of the head with a ruler across the lugs, the DN of the hose or pipe, or the old article number, and we will identify the size. We also fit Storz couplings to hoses: see hose crimping and assembly. See all Storz couplings or contact us via the contacts page.
