The gauge of a swimming pool liner is directlty related to the thickness of the vinyl and generally related to the quality of the product. It is a general understanding in the industry that the higher the gauge of the vinyl pool liner, the thicker the material and therefore the quality is also greater. However, it is good to remember to pick a pool liner that lasts long on average....... this is the most important thing. You can have a thick liner, but if it is not made well, it may not last as long. Moreover, you must maintain your pool well and have good luck to get a longer life out of a liner.