What is the Shield Arms DS20 Magazine?
The Shield Arms DS20 is a 20-round steel magazine for the Glock 17, 34, 45, 47 and 19X. It holds three more rounds than the factory 17-round magazine with only a minimal increase in overall length, and it has an over-insertion stop stamped directly into the steel body. The DS20 fits Gen 3 through Gen 6 frames, also runs in a Glock 19 with the base extending below the grip, and runs with a steel mag catch.
20 Rounds in a Glock 17
The Glock 17 ships with a 17-round magazine. The DS20 holds 20. That's three more rounds before your next reload, in a magazine that's only slightly longer than factory.
The extra capacity comes from the steel body. Steel walls are thinner than the polymer overmold on a factory Glock magazine, which leaves room inside for more rounds without a big jump in length. It's the same steel-body approach Shield Arms brought to the Glock 43X and 48 with the S-Series, the first steel-body aftermarket magazine for that platform.
The DS20 also has an over-insertion stop stamped directly into the steel body. It keeps the magazine from seating too deep in the grip, so it locks in at the same depth every time. Glock builds this feature into its factory magazines; most aftermarket magazines leave it out.
One magazine covers the whole full-size family: the Glock 17, 34, 45, 47 and 19X all take the DS20. It also runs in a Glock 19, with the base extending below the grip.
Key Features
- 20-Round Capacity: Three more rounds than the factory 17-round Glock 17 magazine
- Steel Body: Thinner walls than polymer overmold make room for the extra rounds with only a minimal increase in overall length
- Stamped Over-Insertion Stop: Formed into the steel body to set consistent seating depth on every reload
- OEM-Style Function: Engineered to drop free, lock the slide back and feed the same 9mm ammo your factory magazines do
- Fits the Full-Size Family: Glock 17, 34, 45, 47 and 19X, Gen 3–6; also runs in a Glock 19
- Expandable: Compatible with DS-Series magazine extensions
- Lifetime Warranty: Covered for life against defects in materials and workmanship
Important Compatibility Information
Compatible Models: Glock 17, Glock 34, Glock 45, Glock 47 and Glock 19X (9mm), Gen 3 through Gen 6 where the model exists.
Also Fits: Glock 19. The DS20 seats and runs in a Glock 19, but the base extends below the grip. For a Glock 19 magazine sized to the grip, choose the DS18.
Steel Mag Catch Required: The DS20 is a steel magazine, and the factory Glock mag catch is polymer. We believe the best path to long-term reliability is steel on steel or polymer on polymer, so the DS20 is designed to run with our steel mag catch. It's a one-time swap.
Made in USA with Lifetime Warranty
The DS20 is designed by Shield Arms in Bigfork, Montana, and made in the USA. It's backed by our 100% lifetime warranty: if your magazine ever fails due to a defect in materials or workmanship, we'll replace it.
Technical Specifications
| Specification |
Details |
| Model |
Shield Arms DS20 |
| Capacity |
20 rounds |
| Caliber |
9mm |
| Capacity vs. Factory |
+3 rounds over the 17-round Glock 17 magazine |
| Compatible Models |
Glock 17, 34, 45, 47, 19X |
| Also Fits |
Glock 19 (extends below the grip) |
| Generations |
Gen 3, Gen 4, Gen 5, Gen 6 |
| Body Material |
Steel |
| Over-Insertion Stop |
Stamped into the magazine body |
| Overall Length |
Minimal increase over the factory Glock 17 magazine |
| Mag Catch |
Steel mag catch required |
| Manufacturing |
Made in USA |
| Warranty |
Lifetime |
Performance Advantages
Home Defense and Duty-Size Pistols
Full-size Glocks are often the pistol people keep at home or wear on a belt. The DS20 gives them 20 rounds on board without a long extended magazine hanging out of the grip.
Training and Range Time
Three more rounds per magazine means fewer reloads per string and more time on the trigger during high-round-count training. The steel body is built to stand up to repeated loading, unloading and drops on the range.
One Magazine Across Your Glocks
If you own more than one double-stack 9mm Glock, the DS20 runs in all of them: the Glock 17, 34, 45, 47 and 19X, plus your Glock 19 as a backup or reload magazine.
Consistent Reloads
The stamped over-insertion stop seats the magazine at the same depth every time, so a hard slap on a reload doesn't drive it deeper than it should go.
Frequently Asked Questions
How many rounds does the Shield Arms DS20 hold?
The DS20 holds 20 rounds of 9mm, three more than the factory 17-round Glock 17 magazine.
What Glock models does the DS20 fit?
The DS20 fits the Glock 17, 34, 45, 47 and 19X, Gen 3 through Gen 6. It also runs in a Glock 19, with the base extending below the grip.
Will the DS20 work in a Glock 19?
Yes. The DS20 runs in a Glock 19, but because it's sized for a full-size grip, the base extends below the Glock 19 grip. For a Glock 19 magazine sized to the grip, choose the DS18.
Does the DS20 fit the Glock 45 and Glock 19X?
Yes. The Glock 45 and 19X use a full-size, Glock 17-length grip frame, and the DS20 fits both.
Do I need to replace my Glock mag catch to use the DS20?
Yes. The factory Glock mag catch is polymer and the DS20 is steel. We believe the best path to long-term reliability is steel on steel or polymer on polymer, so we recommend swapping to our steel mag catch. Step-by-step guides are at shieldarms.com/installation.
Is the DS20 longer than a factory Glock 17 magazine?
Slightly. The DS20 adds three rounds with only a minimal increase in overall magazine length compared to the factory 17-round Glock 17 magazine.
What is an over-insertion stop?
An over-insertion stop is a feature on the magazine body that keeps the magazine from seating too deep in the grip. On the DS20 it's stamped directly into the steel body, so the magazine locks in at the same depth on every reload. Glock builds one into its factory magazines; most aftermarket magazines don't have one.
Does the DS20 work with Gen 6 Glocks?
Yes. The DS20 is compatible with Gen 3 through Gen 6 frames of the models listed above.
How is the DS20 different from the S-Series and Z-Series?
All three use the same steel-body construction. The S-Series fits the Glock 43X and 48, the Z-Series fits the single-stack Glock 43, and the DS-Series fits the double-stack Glock 17 (DS20) and Glock 19 (DS18).
Can I buy the DS20 in my state?
Magazine capacity laws vary by state and locality. Check your local laws before ordering, and see our shipping policy for the states we can't ship to.
Is the DS20 made in the USA, and what does the warranty cover?
Yes, the DS20 is made in the USA. Our lifetime warranty covers defects in materials and workmanship for the life of the magazine.
Who Should Buy the DS20
- Glock 17 and 45 Owners: Get 20 rounds on board with only a minimal increase in magazine length
- Multi-Glock Owners: One magazine that runs across the Glock 17, 34, 45, 47 and 19X, and your Glock 19
- High-Volume Trainers: Fewer reloads per string and a steel body built for repeated loading and range drops
- Shield Arms S-Series Owners: Bring the same steel-body standard from your Glock 43X or 48 to your full-size Glock
Related Products & Accessories
The Shield Arms Advantage
Shield Arms built the first steel-body aftermarket magazine for the Glock 43X and 48, and the rest of the industry followed. The DS-Series takes that construction to the double-stack Glock 17 and 19. The DS20 is designed in Bigfork, Montana, made in the USA, and backed by a lifetime warranty.
20 rounds. Same Glock 17. Fewer reloads.
