The 20" BMX Inner Tubes by Imapc Schwalbe are made of durable rubber and butyl material, with a Schrader valve for easy inflation. This set includes two inner tubes, each measuring 1.5-2.35 inches in size and featuring a 35mm valve length. The tubes are designed for 20" wheels and come in a sleek black colour, making them a great choice for cyclists looking for high-quality replacement tubes for their bikes. With a weight of 250g, these inner tubes offer a lightweight and reliable option for cycling enthusiasts.