ATC 2 in 1 Ratchet Spanner 1/4" & 3/8" sq. dr. 2 in 1 Ratchet Spanner 1/4" & 3/8" sq. dr. Double Sided Rachet Wrench  (Pack of 1)

A ratchet is a handle that snaps into one end of a socket by means of a square-drive connector. The other end of the socket fits over a fastener. A mechanism in the ratchet allows the handle to engage and tighten the fastener when you swing it in a clockwise direction and turn freely when you swing it counterclockwise.