The MOTOKING BMX Retro Cup American Bottom Bracket Cups in blue are a set of two aluminum bottom bracket cups designed for BMX bikes. These cups are compatible with PROFILE brand components and are specifically made for old school and standard BMX bikes. The American bottom bracket shell type ensures a secure fit for optimal performance on the bicycle. Perfect for riders looking to upgrade their bike with durable and reliable components, these bottom bracket cups offer a retro aesthetic while maintaining modern functionality.