A cup square is a domed head bolt with a square anti-spin shoulder, cup square bolt and nuts are mainly used to attach wood to wood, for example; the seat and back slats of garden benches to the support structure.
Dimensions:: 8mm x 40mm
Units:: 5 Units
Features & Benefits:: Square section pulls into wood as nut is tightened. Easy to use and time saving. Great for security purposes. No need for a second spanner.