The Rizoma oil filler cap, fitted with a release system via an interlocking key, is made entirely from billet aluminum. It is then anodized for quality and durability. A combination of technology and perfect BMW style for anyone looking to boost bike aesthetics without affecting function. The Rizoma oil filler cap, fitted with a release system via an interlocking key, is made entirely from billet aluminum. It is then anodized for quality and durability. A combination of technology and perfect BMW style for anyone looking to boost bike aesthetics without affecting function. The Rizoma oil filler cap, fitted with a release system via an interlocking key, is made entirely from billet aluminum. It is then anodized for quality and durability. A combination of technology and perfect BMW style for anyone looking to boost bike aesthetics without affecting function.