Thumbscrew for Phillips Flat Head Machine Screw, M5-0.8 x 40mm

Having trouble finding the right screws to make other GoPro thumbscrews work? I found stainless steel machine screws M5-0.8 x 40mm on Amazon, but they were too big at the head to work, so I started from scratch to design these thumbscrews. The 25mm design is more like the OEM thumb screw, the 29mm design gives a little more length but uses the same screw. Also included 123D source files in the zip.

Find the screws on Amazon here (pack of 25 was $5.45 as of today):
http://www.amazon.com/Stainless-Machine-Finish-Phillips-Threads/dp/B000FN7X3O/ref=sr_1_1?ie=UTF8&qid=1413227279&sr=8-1&keywords=phillips+flat+head+machine+screw+5mm+40mm