The Streamlight Contoured Remote Switch replaces the standard battery door found on the TLR-1 and TLR-2 series weapon lights. This unique remote switch follows the contours of the handguns trigger guard, placing the switch directly under the middle finger for instinctive activation of the light that doesnt require the trigger finger or thumb. For constant on, the standard rocker switch has been retained allowing for support hand momentary or locked-on operation.Features :Designed to follow the contour of the trigger guardLow profileEasy to activateMultiple functionsFits most Smith & Wesson M&P handgun framesDoes not fit the M&P compact