In one aspect, a sight with a momentary switch to control a laser beam on the sight may include a main power switch, a switch with momentary sensor, a plurality of locking screw to lock the sight onto a firearm, an orifice for emitting laser beams, a charging socket, and a laser adjustment screw. When in use, the user can press the main power switch to turn on the sight. In one embodiment, the switch with momentary sensor can emit infrared light and if the infrared light is deflected, the laser beam will be turned off. So, if the user wants to turn off the laser beam, the user can simply move the finger toward the momentary sensor to somewhat covers the momentary sensor to deflect the infrared light emitting therein.