Thie is a 1.25" laser collimator by Helix with the circular holographic projection pattern. They are no longer made. You don't need center dots on your mirros with this arrangement because you center things by using the concentric circles. Looks like there are about 7 of them. Very bright laser, and can be adjusted to center the beam. I chucked it up in my lathe and did that adjustment. Works just fine.