These Leak Proof Pushrod Tubes are CNC Machined from 6061 T-6 Aluminum and are available in 4 different colors that include Silver, Red, Black or Blue anodizing. Designed with a larger ID to eliminate pushrod interference. Double ground stainless steel springs keep the right amount of pressure on the double O-Ring tubes, providing a leak-free environment.These Leak Proof Pushrod Tubes are CNC Machined from 6061 T-6 Aluminum and are available in 4 different colors that include Silver, Red, Black or Blue anodizing. Designed with a larger ID to eliminate pushrod interference. Double ground stainless steel springs keep the right amount of pressure on the double O-Ring tubes, providing a leak-free environment.