This is for a generic set of hex drivers purchased from Amazon. The small handles can be uncomfortable at times so I made these sleeves to give the option of a larger grip. They are easy to slide on and suction will keep them secured. They are still fairly easy to pull off with a strong grip so that you can still have the smaller size for tight spaces. I'm unsure if they will fit with the plastic endcaps on the drivers because all of mine have been lost.

I printed these in TPU but any material should be fine. Print with the opening on the bed. The top of the opening is a cone so there is no need for supports. 

I've included a calibration STL so that you can easily test if it will fit before printing the handle.