ALINCO, with keepers. Dimensions are nominal. Supplied in card board boxes.

Size                                    Centre Gap                  Lifting Power

37 x 13 x 10 mm                18 mm                       350 gms.

50 x 13 x 10 mm                18 mm                      500 gms.

73 x 13 x 10 mm                18 mm                      500 gms.