What It Is A precision bottom bracket centrepoint tool for accurately measuring bike fit dimensions and verifying regulation compliance. Best For Bike fitters, mechanics and riders requiring accurate, repeatable measurements from the centre of the bottom bracket. Compatibility Compatible with crankarms featuring an 11.5mm diameter × 7mm deep crank bolt interface. Key Features Magnetic tape measure retention, precision-machined 6082 aluminium construction and a highly visible anodised finish. Design Intent Developed to provide a consistent bottom bracket reference point, eliminating measurement errors caused by estimating the crank axle centre and improving the repeatability of bike fit measurements.