Refurbished
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4
ECHO 1 Mark 18 Polarstar HPA M4

ECHO 1 Mark 18 Polarstar HPA M4

$400.00
Engine

Which Polarstar HPA Engine Should You Choose?

All FPS figures are measured with our standard 180mm 6.02 inner barrel and KA Tech's tuned hop-up, bucking, and regulator combination.

Kythera

250–400 FPS · 350 FPS @ ~100 PSI · Semi-auto only

Purely mechanical — no electronics, no full-auto. Just air, BBs, and go, with a realistic trigger pull, break, and reset. Great for training, Milsim, or fields that are hesitant about HPA rifles.

Jack

250–410 FPS · 350 FPS @ ~100 PSI · Up to 50 RPS full-auto

Our entry-level HPA engine. Fast semi-auto with real full-auto capability.

F2

250–440 FPS · 350 FPS @ ~100 PSI · Up to 85 RPS full-auto

The best overall HPA engine on the market — the strongest combination of air efficiency, accuracy, range, consistency, and tune-ability.

Fusion Engine

250–500 FPS · 350 FPS @ ~55 PSI · Up to 75 RPS full-auto

The powerhouse. A clicky tactical trigger board delivers crisp trigger response for players who want the most power out of their rifle.

Our recommendation: First time going HPA? Go with the Fusion Engine. If you're committing real money to get into HPA, go all the way the first time so you're not stuck upgrading piece by piece down the road.

Up to 45 business days

Production starts the moment you order. Cancel any time before it begins for a full refund — no fee.

Backed by KA Tech Warranty
HPA Specialists Since 2022
Description

ECHO 1 Mark 18 Polarstar HPA M4

This ECHO 1 Mark 18 is a full polymer build with a refurbished body that shows some wear marks. Internals are bone stock apart from the bucking and the HPA engine.

Part of KA Tech’s Liquidation Sale: professionally built rifles with brand new HPA engines and refurbished bodies.

  • Brand new PolarStar HPA engine
  • Professionally built by KA Tech
  • Optional upgrades before shipping: hop-up, bucking, inner barrel, trigger or IGL

Build

  • Body: Full polymer
  • Condition: Refurbished body with some wear marks
  • HPA Engine Options: PolarStar Kythera, Jack, F2 or Fusion Engine (brand new)
  • Internals: Bone stock, apart from the bucking and HPA engine

What's Included

  • Included: The rifle, as shown
  • Sold Separately: FCU, battery, air tank, regulator, airline and magazines
  • Production: Built to order, starting as soon as you purchase
  • Estimated Ship Time: Up to 45 business days (often less)
  • Need It Faster: Contact us to check current in-stock availability
  • Delayed Orders: If we can't meet this window, you may cancel for a full refund, no fee
Manufacturer Warranty
  • PolarStar HPA Engine: 1 year manufacturer warranty on the brand new PolarStar engine

All sales on parts and accessories are final once shipped. Defective or damaged items are covered under the KA Tech Warranty.