TE Connectivity MICRO-EDGE SIMM Socket. MICRO-EDGE SIMM memory card sockets with metal latches to reduce breakage and heat resistant LCP housings. These PCB through hole mount MICRO-EDGE SIMM sockets have a 1.27mm centerline, a low insertion force, centre posts and positive polarization to aid accurate insertion. MICRO-EDGE SIMM sockets with stock numbers ; 681-2304 681-2304 , ; 718-4739 718-4739 and ; 717-6696 717-6696 have right polarization. MICRO-EDGE SIMM memory card sockets with stock numbers ; 681-2307 681-2307 , ; 718-4736 718-4736 and ; 745-5047 745-5047 have left polarization.