ASG Olsztyn does a review and compatibility test of the Begadi PRO Neptun M4/M16 CNC Alu Rotary Hop-Up Unit. Here is what Begadi says about their product... "For the Begadi PRO NEPTUN, it was important for us to improve compatibility and the recurring feeding problems with different manufacturers and magazines.

We have achieved this goal through the flexibility of the NEPTUN. So this hop-up unit can be easily adjusted to the appropriate length without dismantling the gearbox and replacing the nozzle. In order to optimize the feeding of different magazines, the loading channel can be adjusted via a thread. This ensures a very high level of compatibility. The distance between the hop-up unit and the receiver can also be fine-tuned using the integrated screw.

The dial was made to fit current weapons from Begadi, Cyma, E&L, ICS, VFC, E&C, A&K and many more. No adjustments is necessary. As with our FNS and NEBO HopUp Unit, the production also uses the CNC process. All components are manufactured with a maximum tolerance of 0.05mm.

After production, the parts undergo a visual inspection to rule out any internal grades. They are then checked for dimensional accuracy with a laser and securely packaged."