What’s the difference between NEMA and UL enclosures for KDR or KLR?

The National Electrical Manufacturers Association (NEMA) develops standards for the electrical manufacturing industry. Underwriters Laboratories Inc. (UL) is an independent, non-profit, product-safety testing and certification organization. Their ratings are based on similar application descriptions and expected performance. Installations require varying levels of standards and ratings to which TCI offers a range of products that meets those requirements.