The Husqvarna OEM 21" Replacement Drive Belt (531300775) is a genuine OEM part designed for a perfect fit and reliable performance on walk-behind mowers. Built with premium materials, it offers long-lasting durability and smooth power transfer for consistent drive function. Compatible with models like 5521BBC, 5521RS, and R52S, it's easy to install and ideal for restoring your mower’s traction and efficiency.