Upgrade your bike's performance with the MH-P21 Bicycle Headset Bearing, a premium component designed for precision, durability, and smooth operation. Featuring exact dimensions of 37x49x7mm with 45°x45° chamfer angles, this bearing ensures a perfect fit and precise alignment in a variety of bicycle headsets. Crafted from high-grade steel and sealed for added protection, the MH-P21 bearing offers excellent resistance to rust, corrosion, and debris, making it ideal for all-weather cycling. Its smooth operation reduces friction, providing a quieter and more efficient ride while extending the life of your bike's components. The MH-P21 is compatible with part codes ACB3749 and TEX-3801E, making it an ideal choice for replacing or upgrading your bike's headset. Installation is straightforward, allowing for quick and easy upgrades without the need for specialized tools or professional assistance. Specifications: Dimensions: 37x49x7mm for accurate fitting Chamfer Angles: 45° inner chamfer and 45° outer chamfer for precise alignment Compatibility: Compatible with ACB3749 and TEX-3801E part codes