IDC 0.156" ( 3.86mm) Locking Header

 IDC Locking Header 0.156" with Locking Ramp

Used in many makes of pinball machines including Williams, Bally, Stern, Data East, Sega, and more.

These are very easy to cut with a stanley knife so if you want a 2 - 6 locking head I would suggest buying an 11 / 12 / 13 as you will then have what ever is left as a spare.  Makes sense in the long run.