The STHA-3540020 is the core assembly of BYD Seagull's braking system, OE standard compatible, with direct OEM dimension replacement. It features temperature-resistant leak-proof engineering materials and a tightly sealed adhesive process, eliminating leakage and fluid degradation to ensure brake fluid cleanliness and system pressure stability. Equipped with a built-in liquid level sensor for real-time fluid level monitoring, it triggers timely alerts for anomalies, safeguarding driving safety. Compatible with DOT3/DOT4 standard brake fluids, it responds precisely to braking commands, restoring original braking force and pedal feel. With an integrated structure and easy installation, it serves as a preferred OEM-level replacement for brake master cylinder failures or system maintenance.