These are used Pachmayer Full Signature grips (includes backstrap). From Pachmayer's site:
Full Signature Grips with Backstraps
Pachmayr’s Signature Grips feature our patented full wrap-around design and are made from rubber specially formulated for use on semi-automatic pistols. This rubber compound gives them a feel that is unmistakably Pachmayr. Built-in steel inserts ensure they maintain their shape.
Signature Grips are the overwhelming choice of competitive shooters and law enforcement personnel alikeASKING $12 SHIPPED