[RGraff]

I used a GG&G product. This...USP Rail Adapter - HK USP Flashlight Mounts - Attach Streamlight and ITI Flashlights to the HK Pistol

Sorry, just noticed you didn't say USP. Not sure if that will work but hopefully someone here with better info. will chime in.

 

[DeaconBlues]

The H&K 45c uses a MIL-STD-1913 (Picatinny) rail. The TLR-1 light comes with an adapter to fit this. It's marked "1913". Just installed mine today on my P30S.

 

[shooter mcgavin]

check out this thread:
http://www.hkpro.com/forum/hk-handgun-talk/129249-tlr-1-mods-fit-hk45c-rail.html

 

[cjb1911]

The H&K 45c uses a MIL-STD-1913 (Picatinny) rail. The TLR-1 light comes with an adapter to fit this. It's marked "1913". Just installed mine today on my P30S.

the rail on the hk45c is too short for that key.

 

[LSP 972]

Yup, you need one of the older TLR-1s with the cavity BEHIND the securing screw, as per my post in the referenced thread.

Otherwise, the HK45C rails are too short.

.

 

[DeaconBlues]

I stand corrected sir.

 

[OzzManG149]

If your TLR-1 has the new battary door on it you will have to take some material off the adapter for it to work. I used some sand paper, time and patience to get mine to fit.

http://www.hkpro.com/forum/hkpro-members-gallery/151302-hk45c-tlr-1-a.html