Is this compatible with the Arisaka Defense Streamlight Protac HL-X Tailcap Adapter? — 4 Answers

Patrick is incorrect. If you get the Arisaka tailcap adapter, you can put this on your HLX and use any Surefire tape switch. I am doing the same thing just waiting for Arisaka to restock their inventory.

Yes, it will work when you have the Streamlight Pro-Tac HL-X, add the Arisaka tailcap adapter, then add this to connect to a tape switch or Unity button with surefire connection.

Even though Zach already answered, I wanted to reiterate that he is right. You CAN use the SureFire rear cap on a Protac HL-X, but you MUST use the correct Arisaka Defense tailcap adapter. I installed the cap and adapter as soon as they arrived, and can confirm it works. I currently have my Streamlight connected with an NGAL via a Somogear pressure switch, and everything functions normally including the Ten-Tap Programming feature.