tumble air track mouth, most cheap air track is use PVC plastic gas mouth, shortcomings are obvious, that is easily affected when environment temperature change.  Goodtumble air track should be used copper materials, affected by the temperature minimum, while the weight is bigger, but it's worth doing compared to the gain and loss. In order to to order gas is not too cold in winter, copper gas mouth had better have a plastic ring. Waterproof processing, surface water function processing is to china air tracking will not soon be wet, maintain good dry environment. Auxiliary accessories, normally consists of repair glue, and fix the fabric, in addition, a few brands such as John elway can be replaced tumble air track mouth and can also match to the air track nozzle. Finally is the after-sales service, good brand will have a good after-sales service, like American THERMAREST claims to be used for life, its price is expensive, but there is a cost, after-sales service, that Chinese people now always aware of, in fact, good after-sales service, although the unit price is higher, but the total price is much better than a bargain without after-sale service.