If the tire pressure is kept high unicycles are not prone to punctures. Snake bites are common if the unicycle is ridden with the pressure too low. Blow-outs are common with worn tyres. It is always useful to have a spare tube available. The manufacturer will vary depending on availability. All have Schrader valves which are of higher quality and are more appropriate due to their ability to withstand high pressure than "woods" valves as supplied as standard on many unicycles.