The 20x4.0 Fat Bike Tyres and Tubes Set (2 Pack) by Black Cat is designed for electric bikes, mountain bikes, and fat bikes. Made of durable rubber, these puncture-resistant tyres feature an all-terrain directional tread for optimal performance. The set includes two heavy-duty 20x4 inch tyres with inner tubes, suitable for various biking adventures. With a manufacturer warranty of 1 month and a durability guarantee of 99%, this product ensures reliability and longevity for your cycling needs.