The SureFire X300U-B is a high-output pistol light constructed from hard-anodized aluminum in a black finish. It produces 1,000 lumens of white light through a precision Total Internal Reflection (TIR) lens, generating a concentrated central beam with surrounding spill for target identification in low-light conditions. The LED emitter is electronically regulated for consistent performance and contains no filament, preventing failure under recoil.

The Rail-Lock “B” model system uses a screw-tightened clamp for secure mounting on both universal and Picatinny rails. Ambidextrous rear switches allow either momentary or constant-on activation, while optional SureFire DG or XT remote switches can be added if needed. The housing is gasket-sealed for weather resistance and powered by two CR123A batteries. No original packaging or accessories included.

Specifications

• Manufacturer: SureFire

• Model: X300U-B

• Finish/Color: Black, hard anodized

• Output: 1,000 lumens

• Lens: TIR (Total Internal Reflection)

• Emitter Type: LED

• Activation: Ambidextrous toggle, momentary or constant-on

• Mount Type: Rail-Lock (screw-tightened), fits universal and Picatinny rails

• Power Source: 2 × CR123A batteries

• Material: Aluminum

• Water Resistance: Weather-sealed

• Length: 3.6 in

• Weight: ~4.0 oz with batteries