KOLIBRI.works T1 / T2 GLASS
 
Protecting you red dot lens from getting broken is not that hard - just put the T1  / T2 GLASS over the lens, pull the bungee over the RED DOT and you are done.
 
The front plastic ring holds the protective 3mm thick glass in front of your red dot and the bungee provides tension to hold the ring in place.
 
Fits T1 / T2 type red dots with front lens outer diameters of 28mm.