Thanks Senna
per Carbide depot Boring bar standers I found out S=solid steel, 20=1 1/4" dia, U=14" long.
S=Screw lock only, S=Square insert,K= 15Deg end cut, C=7 deg relief, L= left hand, 4= 1/2" insert.
So I need 1/2" square inserts that cut on bouth side witch will give me 8 cutting edges. Now just need the insert number.
Well it looks like I need SNMP 432 or 433 inserts Just need to get ahold of 1 to try before I buy a hole box.