How to Unscrew Three Wing (Three-Pronged) Screws Without a Three-Pronged Screwdriver - Instructables
List of screw drives - Wikipedia
What is a three-sided screwdriver called? - Quora
Recessed Screw Drives - Everything you never knew you needed to know
Gotical 5 Slots M-LOK Polymer Rail Section for M Lok Handguard Three Slots Rail Picatinny Rail Set of 2 Pieces Polymer Material Import from Japan (Pack of 4) : Amazon.co.uk: Sports &