Enhance your mountain bike's performance with this high-quality Bike Rear Derailleur Pulley, crafted from durable aluminum alloy for long-lasting use. Designed with versatility in mind, this colorful pulley is available in two sizes—11T and 13T—offering diameters of approximately 41mm (1.6in) and 49mm (1.9in) respectively, to suit various riding needs and preferences. Key Features: · Durable Aluminum Alloy Construction: Ensures strength and resistance to wear, providing reliable performance on rugged trails. · Versatile Compatibility: Features a 4mm sleeve hole diameter, with the option to expand to 5mm or 6mm by removing the original sleeve, accommodating 4mm, 5mm, and 6mm shaft pulley screws for flexible installation. · Easy Installation: Designed for straightforward replacement and installation, offering a hassle-free upgrade to your bike’s rear derailleur system. · Two Size Options: Choose between 11T and 13T guide wheels to match your original setup or select a smaller size if an exact match is unavailable, ensuring optimal shifting performance. · Wide Application: Specifically designed for SRAM and micro rear derailleurs, making it an excellent accessory for mountain biking enthusiasts seeking reliable and smooth gear transitions. Specifications: · Item Type: Bike Rear Derailleur Pulley · Material: Aluminum Alloy · Color: Colorful · Optional Types: 11T (Approx. 41mm/1.6in diameter), 13T (Approx. 49mm/1.9in diameter) · Applicable Shaft Diameter: 4mm, 5mm, and 6mm Package Includes: · 1 x Bike Rear Derailleur Pulley This Bike Rear Derailleur Pulley combines durability, versatility, and ease of use to improve your mountain bike’s shifting accuracy and overall performance. Whether upgrading or replacing your guide wheel, this accessory delivers dependable functionality tailored to meet your cycling demands.