The key is the CNC Precision machine cut Threads of these DIN dust caps. Delrin is a much better material. So is much better than plastic molded ones.

Note the very smooth base in the bottom of the Regulator DIN Cap for the DIN O-ring of your DIN make section to seal against.

Likewise the excellent threads provide a good seal before the seal between the base & the DIN O-ring.

Excellent for confidently soaking your Regulator 1st Stage in water to remove salt-causing corrosion.

If you have a Scubapro or other 1st Stage - STOP using the push-on dust cap included with your Reg & use this threaded one instead.

You can thread them into each other when not in use (while using your Reg) to protect the threads, keep them clean & dry.

Included in your purchase is 1 DIN dust cap; either a Female (for your Regulator 1st Stage) or a MALE (for your Tank valve)

Buy 2 if you want both: the matching pair of MALE & FEMALE

or Buy more & tell us via message after purchase how many of each.

This exact one is also sold in the USA with Highland laser etched on it - but for A$34 + Shipping (Expensive from the USA) - for just 1.