YHJ-800-3.7 (A)-type coal mine explosion-proof laser pointing(hereinafter referred to as pointing instrument) using semiconductor laser as a light source, portable structure, low power, beam quality, small size, light weight, easy installation, performance, stable and reliable, the product's unique integrated design, large easy to install and adjust it. Products equipped with intrinsically safe DC power supply for non-AC power plants or frequent moving place, continuous work of more than 100h.