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Retro Arms CNC Machined Aluminum Rotary Hop-Up Unit for M4 Series Airsoft AEGs - Red

ID: 59004 (HU-Retro-6388)
Retro Arms59004
3.7 stars, based on 3 reviews
Retro Arms CNC Machined Aluminum Rotary Hop-Up Unit for M4 Series Airsoft AEGs - Red
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May come in black or silver anodized coating, depending on batch


This item is currently Out of Stock Usually restocked within 1-3 weeks.
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  • CNC machined construction
  • Rotary design allows for easy adjustment
  • Constructed from EN AW 7075 for extended lifespan
  • All necessary hardware included
  • Bucking not included
Compatibility: Most M4 series Airsoft AEGs
Material: Aluminum alloy

Manufacturer: Retro Arms

3 Customer Reviews

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by Matthew R. on 08/10/2017
"Got this from brill armory, but thought I'd share my review here too. I think this is the best hop up chamber ever, better than prowin. It features everything the prowin has, but is actually CNC'ed, has little notches to prevent accidental rotary movement, has a collet nut to provide absolute solidity, and is fully 7075 t6 cnc aluminum. Love everything about this thing.
by anthony l. on 06/01/2017
"This is an amazing hopup unit. Sadly, evike forgot to note that this hopup chamber uses a shorter bucking than traditional buckings. Every other website that sells these does mention that. Other than that, I love how this bucking performs. I think it is sturdier and provides a more consistent hop than other units due to a small spring pushing the hopup arm.
by Fennec C. on 05/21/2017
"Looks like a well made hopup, but the window for the c-clip is too far forward, which means the c-clip pinches the bucking. Then I cut the end of my bucking to see if that would work, the c-clip STILL doesn't lock the barrel rotation because the window for the c-clip is waaaay too far forward, meaning that I'm going to have to spend 100x as long CAREFULLY assembling the damn thing because the collet nut tries to rotate the inner barrel when you screw it on.

I think it's better made than the prowin, apart from this GLARING design flaw...

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This item is currently Out of Stock. Most out of stock items are restocked within 1-3 weeks. Some items may take longer. Please add this item to your wishlist to keep posted on its availability.