Laser bed center NEJE 1.5" round

I really enjoy my little NEJE DK-8-KZ 1000mW laser engraver but it can be a pain to get things positions exactly where you want them. by the way these engravers are a ton of fun for $80 off Ebay

This is to allow you to center a 1.5" wood round it fits snugly around the bed and should allow you to get as close as you can to center. It installs without any hardware or rubber bands.

I did notice that what my laser thinks is the center is not exactly centered in the bed (it is off by .5mm)