How to tell what generation Glock you have

The number on the slide (17, 19, 26, 34) is the model, not the generation. Generation is Gen 1 through Gen 6. Magwells, some triggers, and comps on this catalog are sold by gen. Sights and many 10-round magazines usually cross gens if the title does not name one. We sell parts, not pistols.

Read the left side of the slide first. Later guns are stamped Gen4, Gen5, or Gen6 next to the model number. If that stamp is there, you are done. Gen 1–3 almost never print the generation on the slide. A 19X is Gen 5-based and often has no Gen5 stamp.

No stamp: use the frame.

• No accessory rail under the dust cover → Gen 1 or Gen 2. Gen 1 is pebble texture around the grip. Gen 2 adds checkering on the frontstrap and backstrap. Neither has finger grooves.
• Rail plus finger grooves on the frontstrap → Gen 3 or Gen 4. Both have a locking-block pin (a third pin above the trigger pin) and a slide stop on one side only.
• Large reversible magazine release and snap-on backstraps (two seams down the backstrap) → Gen 4 if the grip still has finger grooves. Field-stripped, Gen 4 uses a dual recoil spring.
• Small magazine release, no backstraps → Gen 3. Single recoil spring.
• Rail, no finger grooves, ambidextrous slide stop (a lever on both sides) and a flared magwell opening → Gen 5 or Gen 6. Gen 5 also drops the locking-block pin, so you see two frame pins, not three.

Gen 5 vs Gen 6. Gen 6 is stamped Gen6. The factory trigger is flat-faced; Gen 5 is curved. Grip texture is wraparound RTF6, with a larger beavertail and a textured thumb rest. The optic cut is ORS (Optic Ready System): the red dot screws into the slide. That is not MOS. A MOS plate will not fit ORS. Gen 5 still uses a dual recoil spring; Gen 6 went back to a single spring. Gen 6 launched on the 17, 19, and 45 — do not assume a 34 is Gen 6 because the 17 is.

MOS is not a generation. MOS is Glock’s factory optic cut on some Gen 4 and Gen 5 slides. Full-size MOS (17, 19, 34, 45, 47) shares one plate pattern; 43X / 48 MOS is a smaller cut. A non-MOS Gen 5 is still Gen 5. Standard-frame Gen 6 guns come optic-ready as ORS, not MOS. See Glock MOS red dots and MOS plates.

Crossover models. 19X, 45, and 47 are Gen 5-based (no finger grooves). 19X is a 19-length slide on a 17-length grip. 45 is the black 19-slide / 17-grip duty gun. 47 is the reverse: 17-length slide, 19-length grip. A 17 and a 34 can be Gen 3, 4, or 5 — the model does not tell you the gen. Slim 42 / 43 / 43X / 48 are a different width; MOS on those is the slim cut, not a 19 MOS plate.

Why the gen matters here. A Reptilia magwell marked 19 3&4 will not drop on a Gen 5. A TTI magwell marked G5 will not drop on a Gen 3. A Gen 6 ORS plate is not a MOS plate. Full parts notes: Glock Gen 3 vs Gen 5 parts. Kits split by gen: Glock 19 Gucci kits.

This store lists 10-round magazines and 10-round bodies. Search GEN 3, GEN 5, G5, or G6 in the title once you know the gun.

All Glock parts · Glock 19 · Glock 17 / 34 · 19 upgrades · Gen 3 vs Gen 5 parts