Hardware included. Sold in sets of 2, enough for 2 wheels. Choose from aluminum or brass. Brass wt: 2.2oz (adds 1.1oz per wheel) 
NOTE: THESE ARE DESIGNED TO BE USED WITH THE INCLUDED LOCK WASHERS, THEY MUST BE USED, DO NOT OVER TIGHTEN SCREWS, OVER TIGHTENING WILL DAMAGE THE ALUMINUM INTERFACE.