By A Mystery Man Writer
A wire or wire can be passed through the hole in the bolt head to prevent loosening and falling off.
Counterbore Hole Size for Socket Head (JIS) - The Engineer's Bible
RCBAS5-10, Screws with Through Hole - Hex Screws with Through Hole, MISUMI
Hillman M5-0.8 x 20 mm. Internal Hex Socket Cap-Head Cap Screws
Hillman M6 x 30 mm. External Hex Hex-Head Cap Screw (8-Pack) 4169
Uxcell M8x19mm Round Head Hollow Screw Bolts Through Hole Bolt
Hollow Hex Hexagon Allen Socket Head Cap Screw Lamp Hole Bolt M4 M5 M6 M8 M10
Hollow Hex Hexagon Allen Socket Head Cap Screw Lamp Hole Bolt M4 M5 M6 M8 M10
Secure Cable Bullet Post Hole Covers with these 4-24 x 5/8” screws.
4-24 x 5/8 Stainless Steel Star Drive Socket Head Cap Screw Packs
18-8 Stainless Socket Head Cap Screw Assortment — Red Boar Chain