The Schwalbe Tube No.4 fits 16" and 18" tires with a width of 28-37 mm, making it suitable for children's bikes, strollers, trailers, and more. Due to their excellent manufacturing, Schwalbe tubes have proven themselves in the market for years. They are consistently thick-walled and round in shape. Thanks to their precise assembly, they are durable at the seam. A comparative test showed that the Schwalbe tube retains air pressure significantly longer than other tubes (the others lost nearly twice as much air pressure within 30 days as the Schwalbe tube). A possible reason for this might be a lower butyl content in the other tubes. The special quality of Schwalbe tubes arises from the uniqueness of their rubber mixture. To ensure this high quality, each individual Schwalbe tube is inflated and tested for at least 24 hours before leaving the factory. **Features:** - Butyl rubber ensures double the air retention - 24-hour test for each tube - High elasticity allows coverage of many tire sizes per tube - Recycling process achieves a very good energy balance - Now also available with the new Schwalbe Clik Valve **Suitable for tire sizes including:** - 28-340 | 400 x 30A - 32-340 | 16 x 1 3/8 x 1 1/4 | 400 x 32A - 37-340 | 16 x 1 3/8 | 400 x 35A - 28-349 | 16 x 1.10 - 28-349 | 16 x 1 1/8 - 30-349 | 16 x 1.20 - 32-349 | 16 x 1.25 - 32-349 | 16 x 1 1/4 - 35-349 | 16 x 1.35 - 37-349 | 16 x 1 3/8 - 37-349 | 16 x 1.40 - 28-355 | 18 x 1.10 - 28-355 | 18 x 1 1/8 - 32-355 | 18 x 1.25 - 35-355 | 18 x 1.35 **Valves:** - AV = Auto, Schrader - DV = Dunlop, Blitz, German valve - SV = Sclaverand, Presta, French valve (40 mm) - SCV = Schwalbe Clik Valve **Delivery includes:** - 1 x Schwalbe Tube No.4 including valve