Bolt, 5/16in x 1/2in x 26tpi, flat head set screw CEI BSCY

Bolt, set screw, 5/16in x 1/2in x 26tpi, zinc plated. BSCY / CEI with flat head, set screw threaded full length. Norton inner primary attachment. Original 3420 pre 1946 was 15/32 inch long
Original part number
3420; E6354 - front chaincase inner portion crankcase attachment pin;
3435 - front chaincase and rear chainguard securing pin;
9585 - front mudguard stay fork attachment pin