The monument 4534x grip43 t1 is a 27x32mm double ended nickel plated hexagonal fitting tool fits most radiator valves back nut box spanners taps pumps and cabinets use with the monument 323f tap back nut box spanner when connected to the box spanner the monument 4537g grip plus shorty swivel handle or the monument 345v adjustable basin wrench handle it extends the reach for easier access