Everbilt 3/8 in. 2 in. Internal Hex Button-Head Cap Screw 19748 - The Home Depot
Hexagon Socket Head Bolts | Brugola
Everbilt 3/8 in.-16 x 2 in. Hex Socket Head Stainless Steel Socket Cap Screw 805448 - The Home Depot
Socket Head Cap Screw, 1/4-20 x 1", Alloy Steel, Black Oxide, Hex Socket Coarse Thread, 1/4 inch Hexagonal Allen Bolt, Length: 1 inch, Full Thread (Quantity: 20): Amazon.com: Industrial & Scientific
Head Screws | Allen Bolts | Socket Cap - M5 Black Hex Hexagon Socket Cap Head Screws - Aliexpress