SKU: 36852555053

Ultimate SRS Upgrade Kit (420mm Barrel 3.0–3.5 Joules)

Sale price$158.82 Regular price$176.47
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Ships within 48 hours · Estimated delivery Jul 15 - Jul 20

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Description

Ultimate SRS Upgrade Kit (420mm Barrel 3.0–3.5 Joules)The Ultimate Stalker Upgrade Kit to turn your Silverback SRS into a true sniper beast. This upgrade kit makes your SRS accurate, consistent, and silent! Load up your magazines and dominate the field like never before. The package includes the following Stalker upgrades: Stalker SRS Kraken Hop Up Chamber Ultimate Edition Stalker SRS Scorpion Piston Ultimate Edition Stalker Morpheus 420mm Inner Barrel Stalker SRS Fluted Teflon Cylinder Stalker Official

The Ultimate Stalker Upgrade Kit to turn your Silverback SRS into a true sniper beast. This upgrade kit makes your SRS accurate, consistent, and silent! Load up your magazines and dominate the field like never before.

The package includes the following Stalker upgrades:

We strongly believe that Rapax springs are the best springs on the market. The results achieved with these springs and the Stalker upgrades are outstanding.

*Note: This upgrade discount is only available when all products are in stock. Click "Add to Cart" — if all products are visible, you can purchase this kit with the mentioned discount. If you see a blank page, it means one of the products is currently unavailable.

Product Descriptions:

Kraken Hop-Up Chamber

  • Easy setup for both experienced and new players (~2-minute bucking swap)
  • 100% self-alignment system for a perfectly straight setup
  • 100% straight / 100% seal patented Kraken bucking
  • Adjustment wheel head cut-out for easy tuning
  • O-ring guided adjustment wheel
  • Custom-made steel hop arm screw
  • Laser-engraved white lettering and text
  • Front O-ring to prevent BBs from falling into the receiver
  • Modular chamber design compatible with most VSR buckings, bridged/unbridged barrels, and nubs
  • Modular arm section compatible with S1, S2, and S3 arms
  • V-groove island for upper outer barrel screw (SRS A1)
  • V-groove for lower outer barrel screw (SRS A2)
  • Side flat body cutouts for future Stalker products
  • Quick setup for easy barrel or bucking changes and barrel cleaning

SRS Scorpion Piston

The Stalker Scorpion piston features an extremely modular design developed from scratch. It offers all the options players could want for their SRS piston. This unique concept uses six weights that form the piston body itself. Because the piston is constructed from these weights, it can be extended with additional weights (short-stroke configuration), which reduces cylinder volume and joule output.

Morpheus 420mm Inner Barrel

The Morpheus Hybrid Barrel is made from highly durable SUS304 stainless steel and features a dual-bore tapered end crowning to enhance both range and accuracy.

We selected stronger, more durable SUS304 seamless steel to raise the performance standard. Most brands use SUS303 seamed steel because it is easier to machine. However, SUS303 stainless steel has reduced corrosion resistance due to its machinability-focused composition. The SUS304 steel we use is more difficult to machine but significantly more durable and offers superior corrosion resistance.

Fluted Teflon Cylinder

This cylinder is a Teflon fluted version of a standard cylinder and gives your SRS A1 or A2 an aggressive look. The internal coating is applied using a cold treatment process, ensuring the cylinder maintains perfect straightness—unlike many heat-treated cylinders. In addition to enhanced aesthetics, the special inner coating improves energy transfer with the piston and may increase joule output when paired with a properly sized piston cup.

  • Fully compatible with Silverback SRS A1 and A2 receivers
  • Thread compatible with both A1 and A2 bolt handles
  • Compatible with aftermarket pistons

Rapax 3J+ RMS Spring

The Rapax Modular Spring (RMS) series is manufactured to the same high-quality standards as the Light Pull series. Built for durability and performance, it delivers an outstanding sniper experience. Compared to the Light Pull series, the RMS spring is significantly shorter, slightly harder to pull, and provides quieter shots. RMS springs are also electrically coated to prevent rust, ensuring smoother operation on the spring guide.

If you have any issues or questions about this or other Stalker products, please visit our Stalker Owners Group on Facebook here: https://www.facebook.com/groups/329589544772075/

You can follow live updates, photos, and information on Instagram, Facebook, or YouTube:

Facebook: https://www.facebook.com/StalkerAirsoftDesigns/
Instagram: https://www.instagram.com/stalkerairsoftdesigns/
Youtube: https://www.youtube.com/channel/UCWsBiSHlu-lbcnGQWAkeJWQ

For more information about Stalker products, tech & crafting guides, please visit: www.stalkerairsoft.com

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 36852555053

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4.5 ★★★★★
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Elaine Laventure
Louisville, US
★★★★★ 4
WHAT I LEARNED
Color: U.S.A, Size: Medium
i AM NOT SURE THAT 4 STARS IS A FAIR SCORE, MY DOG IS AN AGGRESSIVE CHEWER, NEEDLESS TO SAY WITHIN 2 DAYS ALL THE TABS WERE OFF, BUT THERE WERE NUBS LEFT AND SHE CAN USE THAT. HERE IS A WHAT NOT TO DO, BRING IT TO THE DOG PARK, THEY ALL HAVE A BLAST BUT IF YOUR A BULLY/PIT MIX AND DECIDE TO SINK THEIR TEETH INTO IT, IT DOES DEFLAT. LESSONS LEARNED STILL A FUN TOY.
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Reviewed in the United States on May 13, 2026
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Jedi and Waggy
West Palm Beach, US
★★★★★ 5
Sturdy ball with pump
Color: Black/White, Size: Medium
Thick material so it won't pop so easy. Comes with a hand pump and 2 ball needles. Tabs for the dog to carry in his mouth. Although my dog bites the whole thing to carry. Savage loves it!
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Reviewed in the United States on February 4, 2026
G
Verified Purchase
Grant C.
Louisville, US
★★★★★ 5
Durable and fun
Size: Medium, Style: Ultra Tug, Size: Medium, Style: Ultra Tug
This is a cool toy. My dog took to it right away. It tosses great. I like that you can play a little tugging along with fetch. We mainly use it outdoors. It feels very strong and durable. For size reference my dog is a mini golden doodle and weighs about 30lbs.
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Reviewed in the United States on February 22, 2026
J
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Joshua J. Selby
Lexington, US
★★★★★ 5
Great toy!
Size: Medium, Style: Ultra Tug
We have a 1 yr old rescue (German shepherd mix) and she didnt really know how to play with humans, she was scared of everything. We got this toy to help us teach her how to play fetch and tug of war and it really helped her come out of her shell. She loves this toy! It is very durable and fun to throw. Just enough rope to tug with her and doesn't come apart like other rope material. We got medium size and prob buy another one.
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Reviewed in the United States on May 8, 2026
C
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Clever Naming Scheme
New York, US
★★★★★ 5
Durable
Size: Small, Style: Ultra Duo Tug
Well, our dogs didn't end up playing tug with each other, but they love the toy anyway and it still looks pretty good after a month. That doesn't sound like much, but they both love to chew and destroy rubber and they're ridiculously good at it. They also really like chewing the strap between the two balls, which is still in surprisingly good condition. Most "indestructible" toys are toast within the hour. Well worth the money. Plus, the unpredictable bounce when thrown keeps the dogs busy.
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Reviewed in the United States on May 23, 2026

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