SKU: 76529175663

MAXX CNC Aluminum Hopup Chamber M4P - PRO (for Polar Star)

Sale price$94.49 Regular price$104.99
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Description

MAXX CNC Aluminum Hopup Chamber M4P - PRO (for Polar Star)Product Description CNC Aluminum Hopup Chamber M4P Pro (with BB Latching System) unit is precisely machined to perform accurately and consistently with HPA PolarStar Engines on standard M4 M16 platform. The Hopup Chamber M4P unit is built with an aluminum Rotary Dial Knob for fine hopup adjustments, the precision Hopup Lever and 4mm Bucking Nubs (6mm Bucking Nubs are optional) to perform best with R Hop and Standard Hop to keep the BB shooting

Product Description

 

CNC Aluminum Hopup Chamber M4P Pro (with BB Latching System) unit is precisely machined to perform accurately and consistently with HPA PolarStar Engines on standard M4/M16 platform.
The Hopup Chamber M4P unit is built with an aluminum Rotary Dial Knob for fine hopup adjustments, the precision Hopup Lever and 4mm Bucking Nubs (6mm Bucking Nubs are optional) to perform best with R-Hop and Standard-Hop to keep the BB shooting accurately and consistently on every single shot.
The Hopup Chamber M4P unit is designed to accept the HPA PolarStar Engine M4 nozzle length, and fully compatible with most aftermarket soft and hard rubber buckings without losing FPS or dropping BB during use.
The Hopup Chamber M4P unit is wisely equipped with an interchangeable Inlet Adaptor OD11mm to ensure the hopup unit is inserted exactly in the center of the 11mm inner bore HPA Engine nozzle outlet without wobbling. (Inlet Adaptor OD11.5mm and OD12mm are optional)
Also mounted the removable CNC Brass Side Wings to slide smoothly into the outer barrel slots, and included an advanced CNC Delrin Locking C-Clip to hold the inner barrel tight in place without wobbling and twisting.
More than that, the Hopup Chamber M4P Pro unit is specially designed with a new BB Latching System to prevent BB dropping after removing the magazine. The Latching Arm can also be manually pressed to release the remaining BB from inside the hopup chamber.

***The Dual UV LED Tracer Module is an add-on option to glow BB in the dark. Operating Voltage from 7VDC - 15VDC (2-4 cells LiPo, 6-13 cells NiCad). (Sold separately)
***Test results: FPS might be increased from 10FPS to 30FPS over the stock setup. Please check your FPS!

 

  Includes
1 x CNC Aluminum Hopup Chamber M4P Pro (with BB Latching System) unit
2 x CNC Acrylic Side Cover
2 x CNC Brass 2.5mm Side Wing
1 x CNC Steel Pivot Pin
1 x CNC Aluminum Hopup Lever
1 x CNC Aluminum Soft Round Nub
1 x CNC Aluminum Soft Flat Nub (4mm)
1 x CNC Aluminum Hard Concave Nub (4mm)
3 x Steel Nub Spring
1 x CNC Steel Spring Guide
1 x Steel Upper Compression Spring
1 x Steel Center Compression Spring
1 x CNC Delrin Locking C-Clip
1 x CNC Brass Barrel Spacer
1 x Brass Barrel Spacer Holder Oring
1 x CNC Aluminum Rotary Dial Knob
1 x CNC Aluminum Inlet Adaptor (OD11mm)

 

  Specification
Overall Length: 51.15mm
Overall Height: 37.75mm
Inlet Adaptor Outer Diameter (to fit into HPA Nozzle Outlet): 11mm
Hub Outer Diameter (to fit into Outer Barrel): 12mm
Hub Inner Diameter (to fit Nozzle): 8mm
Feeder Outer Diameter (to fit magazine): 8.85mm
Feeder Length (to fit magazine): 6mm
Material: Aluminum 6061

 

  Features
Machined from a solid aircraft aluminum block with tight tolerances to achieve the most accuracy, consistency, and durability
Performed accurately and consistently with HPA PolarStar Engines on standard M4/M16 platform
Precision Rotary Dial Knob for fine hopup adjustments
Re-engineered the precision Hopup Lever and 4mm Bucking Nubs (6mm Bucking Nubs are optional) to perform best with R-Hop and Standard-Hop to keep the BB shooting accurately and consistently on every single shot
Removable Steel Pivot Pin for ease of setup and maintenance
Accepted the HPA PolarStar Engine M4 nozzle length
Fully compatible with most aftermarket soft and hard rubber buckings without losing FPS or dropping BB during use
Wisely equipped with an interchangeable Inlet Adaptor OD11mm to ensure the hopup unit is inserted exactly in the center of the 11mm inner bore HPA Engine nozzle outlet without wobbling. (Inlet Adaptor OD11.5mm and OD12mm are sold separately)
Mounted the removable CNC Brass Side Wings to slide smoothly into the outer barrel slots
Included an advanced CNC Delrin Locking C-Clip to hold the inner barrel tight in place without wobbling and twisting
Equipped with 2 compression springs on top and center to ensure the hopup unit is seated straight and air tight during use
Specially designed with a new BB Latching System to prevent BB dropping after removing the magazine
The Latching Arm can also be manually pressed to release the remaining BB from inside the hopup chamber
Compatible with any 11mm inner bore HPA Engine nozzle outlets
The Dual UV LED Tracer Module to glow BB in the dark ready!

 

  Weight
N/A grams

 

  Usage
Compatible with most HPA PolarStar Engines on standard M4/M16 platform

 

  Requires
Wearing eye protection is recommended
Use proper tools for disassembly and reassembly the gear box with great care due to spring tension
Bearing lubricant oil/grease is recommended for smooth operation

 

  Instruction
Instruction Manuals are included

 

PolarStar Airsoft is a division of PolarStar Engineering & Machine (PSE&M).
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
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  • 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: 76529175663

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4.3 ★★★★★
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Verified Purchase
Amazon Customer
San Leandro, US
★★★★★ 4
Good Shelves
Color: B. Rustic Brown - Americana Farmhouse Style, Number Of Shelves: 3, Size: 22.5inches
These shelves are really nice quality and look as advertised. The hardware included was great quality, metal drywall anchors and good screws. They were easy to install, and make even/level with each other. My only gripe is the price, but I'm very satisfied with the product overall.
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Reviewed in the United States on April 12, 2026
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Verified Purchase
Patricia G.
Lowell, US
★★★★★ 5
Attractive, easy to install, nicely equipped hardware package.
Color: B. Rustic Brown - Americana Farmhouse Style, Number Of Shelves: 2, Size: 22.5inches
These are pretty doggone nice shelves and I appreciate the fact that they are not made of solid particle board. Yes they are made of an engineered product, but they are lightweight and strong…and look better than particle board products and more costly than their actual price. Easy installation system with the bracket…not fussy like some are. An especially thoughtful touch is the variety of hardware that is included. Also a tiny level for use when installing them. What? …So they can be installed correctly? I was pleasantly surprised by this inclusion.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 29, 2026
S
Verified Purchase
Sara
Charlottesville, US
★★★★★ 5
Beautiful shelves
Color: B. Rustic Brown - Americana Farmhouse Style, Number Of Shelves: 2, Size: 22.5inches
Great quality shelves, have them in 4 rooms, they are easy to hang up and lightweight, look really nice and keeps room looking organized and clean.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 24, 2026
K
Verified Purchase
Kristal S.
Waukegan, US
★★★★★ 5
Perfect for a coffee bar
Color: B. Rustic Brown - Americana Farmhouse Style, Number Of Shelves: 3, Size: 15.7inches, Color: B. Rustic Brown - Americana Farmhouse Style, Number Of Shelves: 3, Size: 15.7inches
These are great for my coffee bar! These shelves are easy to install and came with all the hardware needed. What a great value for your money, especially when you get 3 of these cute shelves. I love how they help organize my coffee bar area and the size fits perfectly.
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Reviewed in the United States on May 26, 2026
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Saved
Port Orchard, US
★★★★★ 4
If the set screws were white the shelves would be perfect.
Color: C. White - Modern Minimalist Style, Number Of Shelves: 3, Size: 15.7inches
I'd give 4 1/2 if there was one. The shelves thwmself are nice I just don't like the visible little black set screws. The shelves themself look great and are not wobbly at all if you install correctly. I purposely installed the bracket upside down because of the little black setting screws; I didnt want them showing because the shelves are above eye level and the screws are black and I didn't want them showing. But that made the shelf lean amd wobbly so I turned them back over the way they are supposed to be and that made them level and sturdy. I guess I'll paint the little screws.
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Reviewed in the United States on January 21, 2026

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