#6-32 x 1/2 UNC Cap Screws A2 Stainless x20  Ref: NB7356
Thread - Spanner Size ---Thread Pitch UNC / UNF

Thread Spanner UNC UNF

#6 1/4AF 32 TPI 40 TPI
#8 1/4AF 32 TPI 36 TPI
#10 5/16AF 24 TPI 32 TPI
1/4 7/16AF 20 TPI 28 TPI
5/16 1/2AF 18 TPI 24 TPI
3/8 9/16AF 16 TPI 24 TPI
7/16 5/8AF 14 TPI 20TPI
1/2 3/4AF 13 TPI 20 TPI
9/16 13/16AF 12 TPI 18 TPI
5/8 15/16AF 11 TPI 18 TPI
3/4 1" 1/8AF 10 TPI 16 TPI
7/8 1" 5/16AF 9 TPI 14 TPI
1 1" 1/2AF 8 TPI 12 TPI