Have a gun that uses a ghost ring?
Replacements can be expensive and hard to find...
Khaos Bikes has a solution!
 
Custom 3d printed ghost Ring rear sights! 
Fits in a standard ghost ring base plate, and available in several colors and several aperture sizes.
-Bright green, Black, Red
-1mm, 1.5mm, 2mm, 2.5mm, 3mm
 
If you want a variety, Check out the variety pack to save some money!