In order to make precise enough line alignment at close distance, it makes good job with a 5mW 650nm red laser line generator. It projects red laser light directly from a 650nm red laser diode. Being made with a qualified glass coated lens within 10 to 110 degree, equipping with a glass window, it is working well under moisture or dust. After correct use of optic lens degree and freely adjusted red line fineness and red line projecting direction, this red laser is making highly clear line generation for all close distance and inner room line aligning works effectively.https://www.berlinlasers.com/650nm-red-laser-line-generator