Your spa or hot tub cover is made with marine grade vinyl. It’s tough, but not tough enough. Over time, UV rays will deteriorate the vinyl, and you may notice threadbare areas or broken stitches. In some situations you may find that applying a vinyl patch using HH-66 Vinyl Cement and Shelter-Rite Vinyl Fabric may give you a few more seasons use.
For more info on HH-66 click here: http://www.sailrite.com/Brand/HH~66
For more info on Shelter-Rite click here: http://www.sailrite.com/search?keywords=shelter-rite