The Weasler #20401708 idler sprocket gear is specifically designed for a #40 roller chain with 17 teeth and a 1/2" bore diameter. This high-quality sprocket gear is manufactured by the trusted brand, Weasler, ensuring durability and reliable performance in industrial automation and motion control systems. Perfect for mechanical power transmission, this idler sprocket gear is a crucial component for ensuring smooth and efficient operation of your machinery or equipment.