BBC ADAPTER We at FireEye know that not everyone can, or wants, to go out and buy a completely new crankset when getting a new frame. If you already have, or just want to run a threaded crankset in a BMX BB shell frame, no problem. FireEye's BBC (Bottom Bracket Converter) gives you the freedom to use a 73mm threaded BB in an American BMX BB shell. Cups install like a threadless headset and the four heat-treated cromoly bolts provide extra strength and stability by distributing load stresses throughout the entire BB shell. The bolts also keep the cups synchronized in proper placement and free from individual rotation. Lastly, they're anodized black and lasered etched in proper FireEye fashion. Bottom Bracket Converter that lets you use a 68 or 73mm threaded Euro BB in an American BMX BB shell Material: aluminum 6061-T6 Color: black Surface finish: CNC machined and anodized Logo: all lasered logo