The ULTIMATE® Upgrade Series cylinder head have been CNC manufactured in machine-aluminium and thereafter anodized with a colour code for easy recognition. The heads have been designed with double rubber seals to minimize loss of compression from the cylinder. The special ‘trumpet design’ ensures optimal delivery of air to the barrel/BB. Furthermore, the cylinder heads have a powerful built-in rubber band that absorbs the shock from the piston head. For version 2 gearbox with built-in rubber ring on the outer flange, resting against the gearbox. This design absorbs shocks and prevents unintended cracking of the gearbox front. ULTIMATE®’s cylinder parts are designed to give the best possible air compression and durability. For this reason we recommend always using ULTIMATE® cylinder parts and not combining or mixing with other upgrade parts as this can affect the result and performance of the upgrade.