Warehouse, wholesale, retail, sales:
-fasteners
-screws with hexagonal, cylindrical,
recessed head, neck, into concrete,
plow, self-tapping with cylindrical head
head down
TEX with hexagonal head, IMBUS
-nuts self-locking, crown, closed,
low, on scaffolding, wing, welding,
striking
-flat, feather, fan pads,
wedge, ...