The stock hop-up arm in the VFC MP7A1 is made of resin, which can flex and twist when hop-up is applied. This leads to inconsistent pressure on the bucking, reducing accuracy and range. Prometheus addresses this issue with a high-rigidity aluminum alloy arm, machined to eliminate twisting and ensure even, horizontal pressure on the hop rubber.
Beyond material improvements, the arm?s geometry has been optimized. The front-to-rear positioning and initial engagement angle of the hop tensioner have been refined to maximize efficiency, allowing the bucking to be compressed more effectively for consistent backspin.
Another advantage is compatibility with multiple hop tensioners. While it works seamlessly with the stock VFC tensioner, it also supports Tokyo Marui-spec aftermarket tensioners, giving users greater flexibility in tuning their hop-up system.
This upgrade is specifically designed for the Umarex/VFC H&K MP7A1 V2 AEG (New Generation model), including both the Japan and HK-licensed versions.
By replacing the stock resin arm, this upgrade ensures more stable hop-up adjustment, improved shot consistency, and better long-range performance. The rigid aluminum construction prevents deformation under stress, while the redesigned arm angle optimizes bucking contact for enhanced efficiency.
For VFC MP7A1 owners seeking a noticeable improvement in hop-up reliability and precision, the Prometheus Strike Hop Up Arm is a highly recommended upgrade.

Key Feature

• Prometheus Strike Hop Up Arm For Umarex (VFC) MP7A1 V2 AEG Airsoft
• Aluminum Construction Airsoft Strike Hop Up Arm
• Design For Upgrade the Original Parts More Durable
• This aluminum alloy (cut from high-rigidity material) arm prevents twisting, ensuring consistent and horizontal pressure on the hop rubber
• The front-to-rear position and arm angle of the hop tensioner have been refined to: Improve efficiency in applying hop-up./ Ensure reliable and stable BB backspin
  
• This results in better accuracy and range compared to the stock arm
• Works with Stock VFC hop tensioner (genuine part)/ Tokyo Marui-standard aftermarket tensioners, giving users more tuning options
  
• Suitable For Umarex (VFC) MP7A1 V2 Automatic Electric Gun AEG Airsoft SMG Sub Machine Gun