its a print that takes light from a led and condenses it to a point that can be adjusted by moving or flipping the lens which i got from one of those phone vr headsets that you get, use for 5 minutes, get nauseous and the put in a drawer never to be seen again. you can use multiple lenses to see what it does to the light, its quite fun to mess around with. its also useful to shine behind the nozzle allowing you to see the gap between the nozzle and the bed well so you can adjust the first layer height. i also imagine it would be good at illuminating pcb's you can put a stronger light at the end to make it brighter but with just a standard led it can wash out my my printers lcd and when i pointed it at my eye for just a few seconds in left a bright spot in my vision for 15 mins so don't do that. also the arms don't hold the lens too well at the out most position put pinching them with a rubber band or your finger works

Print instructions

.4 nozzle
.25 layer height
pla