Type 1 Black:
Material/Color: Aluminum Black
Size: 35x30x18mm(LxWxH)
The Inner diameter of this one is 12.35mm, it has two bolts on the top to fix the laser.
Type 2 Silver:
Suitable for: 12mm Laser Module
Material: Aluminium
Size: please see the below picture
Type 3 Glolden:
Size: 48x20x27mm(LxWxH)
Inner Diameter:12.3mm
Suitable for: 12mm Laser Module
Material: Aluminium
Type 4 WX:
It is a holder can be 360°flexibly adjusted,with a 12mm circle to fix the module.