X Limb revolutionises prosthetics through modular design and industrial production, solving the problems of high cost, poor fit and uniform aesthetics with ‘universal fit + affordability’. The socket integrates the BOA Dynamic Adjustment System with a ruler-like structure and knobs to fit 90% of all residual limbs without customisation. The standardised three-way joint supports plug-and-play compatibility with any leg tube diameter/shape, allowing for DIY assembly or online purchase. Joints with a four-link mechanism mimic natural gait, and a knee housing ensures safety. The use of 3D printing