This is a customizable clip based on my snap-in flashlight clip It allows you to attach a small flashlight to your hardhat to use as a head lamp. Two screws clamp the clip securely  to the brim of a hardhat.   Not all hardhats have the accessory slots, so I made this one so my slot-less brethren will still be able to see the light.  Instructions:-Measure diameter of flashlight  -Customize by editing scad-Print out using 100% infill.   -I used 8-32 nuts and 1/2" long 8-32 machine screws, but you can change the size of the nut traps and holes in the scad.  -Clamp to hardhat, and snap in your flashlight!  The included STL fits my Sipik SK-68 clone, and mounts to many different hard hat models.