Pb fastener zinc plated steel mf spacers m4 packs of 10 pb fastener s47040x50 these zinc plated steel mf spacers m4 x 50mm from pb fastener amp components are 50mm long hexagonal m4 tapped spacers manufactured to a high standard using galvanised steel and designed with a 1x 8mm external male thread and 1x 9mm internal female thread at each end these quality spacers fit a 7mm spanner opening and come supplied in packs of 10 pb fastener s47040x50 zinc plated steel mf spacers m4 x 5