We've tooled up our own custom M5 screws specifically made for mounting ski bindings to swap plates or inserts. The head is flat underneath and fits like a buttonhead screw. The underside of the head has locking serrations to help ensure that the screw doesn't back out over time. High quality stainless steel. For use with a Pozi #3 phillips head screwdriver.
It is very important to maximize the number of threads engaged in an insert or a swap plate, so be sure to measure carefully. Inserts can accommodate from 3mm min to 6mm max of thread engagement. We like to target 4mm of thread engagement. Do not excede the min/max numbers for any reason - you will not get a secure mount. These screws fit exactly like allen buttonheads in terms of length.