The Maple Leaf Autobot 2021 series hop-up rubbers represent the latest development in Maple Leaf’s hop-up rubber design. In the Autobot 2021 series, the material composition has been redesigned, replacing the standard rubber compound with a silicone-based material. The silicone-based material improves hop-up performance in varying weather conditions and temperatures. Its advantages are especially noticeable in cool or cold environments, as silicone rubber remains flexible even in low temperatures.
The design of the 2021 series is based on the proven original Autobot series. The most distinctive feature of the Autobot series is its long, hourglass-shaped curved hop-up nub, which provides strong spin even for heavier BBs.
Features:
- Silicone-based material that slows down freezing
- Includes a steel C-clip to improve nozzle seal against the hop-up rubber. Use of the C-clip is optional.
- Support pieces inside the rubber on both sides of the barrel’s hop-up window
- Compatible with Marui / WE / KJ GBB pistols, WE GBBR rifles, and VSR-10 compatible spring sniper rifles
Standard round nubs in airsoft guns do not work optimally with Maple Leaf’s new hop-up rubbers featuring an extended contact patch, as a point-shaped nub curves the contact area of the hop-up rubber. This prevents full benefit from the MR hop’s long contact surface and may cause the rubber to bend into an unintended position. We recommend using Maple Leaf’s curved nub or curved adjustment arm for best performance. For GBB pistols, it is recommended to use the Maple Leaf I-Key nub.
Hop-up Rubber Degree (Hardness Rating)
The degree rating indicates the softness of the hop-up rubber. The lower the degree, the softer the rubber. Different hardness levels perform differently across various power ranges. In other words, the degree can be used as a guideline when selecting the right rubber for your airsoft gun based on its power. As a rule of thumb: the more powerful the gun, the harder the hop-up rubber should be. The table below shows the Taiwanese manufacturer’s own recommendations for suitable power ranges.
| Hardness and Color |
Recommended Power Range |
| 50 – Green |
Below 110 m/s (1.2 J) |
| 60 – Yellow |
90-120 m/s (0.8-1.5 J) |
| 70 – Blue |
110-140 m/s (1.2-2 J) |
| 80 – Red |
140+ m/s (over 1.8 J) |