Front and rear guides, spring, and tar.

May substitute brass on certain parts If out of steel.

Guide itself will always be steel. Why? Many first time installers over stress plastic guides on heavy wire springs causing damage on the install. This saves that from happening and the synthetic front allows more vibration control and is not subject to damage like the rear.

Top hat synthetic with piston spacer.

Allow extra build time.

Extra Springs,

http://www.airguns.citymax.com/catalog/item/251488/1124294.htm