This is a simple sight designed for my Airsoft Grenade Launcher https://www.thingiverse.com/thing:3721739 , its ranged from 50-250 feet, Requires 4 X M3 fasteners and works great for CO2 shells. Make sure the range numbers are facing the shooter. !!!Note: I'm always open for suggestion and help on improving the design and proof of concept. !Don't forget to check out my other Cool designs and Follow my Daily dose of KooKoo uploads, Enjoy ;)