Power tool accessories Fixing fixture of 20mm hollow bracket with three slots Hexagon socket cap screw - AliExpress
Tri-Wing® Machine Screws - Loss Prevention Fasteners
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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 &
Metric Screw With Three (3) Slots In The Head, Fits Olympus® I.D. Plates