708.866" 18-22mm Ø Boring Head 310.031 5/8" Carbide Shank WCGT 020102 #2. Cartridge is 625.020 which takes any WCxx 0201xx carbide insert such as WCGT or WCMT 020101 020102 020104 etc.
Solid carbide shank is 5/8"x3.5" (part # 615.236) and the entire assembled unit is about 5 OAL.