Check the listing for details. Strike Industries Gen3 to Gen4 Slide Adapter/Conversion Plate for Glock (G-SAP). Color: Black, Condition: New. Listed at 19.95 USD. Product Features:Adapt GEN3 slide to GEN4 framePrevent flex in frameEliminate the gapLightweightCompatibility:Glock Gen 3 slidesIncludes:1x Slide Adapter PlateThe Strike Industries Slide Adapter Plate (G-SAP™) allows you to use a GEN3 slide on a GEN4 frame. Naturally a GLOCK™ factory or aftermarket GEN3 slide will fit and function on a GEN4 frame, but there are a few issues to address. First is the ugly gap and the second is the flex in the frame because of the large hole. Install the G-SAP™ in seconds and prevent any movement of the GEN3 recoil rod and spring from possibly damaging your GLOCK™ GEN4. Because there is an abundance of aftermarket GEN3 slide options, Strike Industries wants to make sure you are not restricted by fitment and have your choice to fully customize your pistol. Giving you a cost-effective resolution with SI design, the Strike Industries Slide Adapter Plate won't hold you back on form and function.