Snap-on Tools USA NEW 22 Piece 1/4 Drive. SAE & Metric DEEP 6 Point Socket Lot Set. Set Model #’s. STM14 = 7/16″ STM16 = 1/2″ STM18 = 9/16. STMM5.5 = 5.5mm. by admin // December 21, 2023 Standard Sae Metric