Standard sizes available from stock pan head , dome head , hex head with pozi (Philips) or slot typical sizes as below:-
1/2" No. 8 - 13mm x 4.2mm
1/2" No. 10 - 13mm x 4.8mm
Many more on request including special sizes available in stainless steel 304 (A2) , 316 (A4) Zinc plated.
We can also supply with EPDM, Neoprene or Polymide washers to suit.