Compact Weapon-Mounted Light

Fits perfectly on a Beretta PX4 9mm, and most importantly, it does not kill batteries (unlike certain other brands which I will not name) while not being used. I have had unfortunate experiences with some well-known flashlight manufacturers that simply run batteries down to zero while sitting unused on a shelf. This makes the light useless when its actually needed. High marks to Nightstick for avoiding this issue. HIGHLY RECOMMENDED due to inherent reliability.

UPDATE 4/15/2020
The light DOES fit on the XD. You have to kinda force it on. Use the C1 fitting, undo the bolt all the way, put the bolt side on first, CLAMP the light onto the rail (clamp the light to the gun as hard as you can), and tighten the bolt WHILE clamping the light to the firearm. Customer service with Nightstick is PHENOMENAL and they actually called me to make sure I got the light to fit on correctly. Their customer server is second to none and the products they stand behind are just as great. I am now a lifetime customer because of their customer support.
Original review:
Does not fit the Springfield XD (Does Mod2 according to the fitting chart, but I'm referring to the first XD); the light slides on on and off without the fittings, but once a fitting is put on, the light no longer slides in and the lip of the light does not go over the lip of the rail on the XD. Disappointing, as this light looks amazing on the gun, is very bright with a white, cooler temperature, and is very well built.

Compact, 550 lumens and just 2.5 ounces makes the TCM-550XL a dream for every day carry. I train often on an outdoor range with a lot of holster draws as well as hundred of dry draws per week, so my gear sees heavy use. The 550XL is as solid as a rock and the controls are worlds better than the competition. My TLR-1HL has officially been placed on backup duty.