TACFUN Crossbow Archery Arrow Red Laser Sighting Bore Sighter Long Battery Lasting Time The sight tool will continuously work for more than five hours Come with 2*LR44 BATTERIES Class IIIa 635nM Less Than 5mW, Avoid Direct Eye Exposure to Beam. Operation: On/Off End Cap Laser Type:Visible Red Laser Power: &lt; 5mW Construction: Brass