Glock OEM slide stop. Fits early 2 pin guns models G17,17L,34 These pistols do not have a locking block pin and were manufactured between 1986 to mid 2002.
Look at the photo of this slide stop and compare to the slide stop currently in your pistol to verify. Pay special attention to the "spike limiter" located just above the trigger pin hole. If the slide stop in your pistol has this "spike limiter" you are ordering the correct part.
If the slide stop in your pistol does not have the "spike limiter" you need to order part number GLO-2919 (std) or GLO-7496 (ext). Compare the photos of these parts to verify before placing your order.