The safety certifications currently popular in the US market include UL, CSA, MET, etc.
UL - the most common, most authoritative and most recognized certification on the market
If When your customers consider authority and require UL certification, or when you have high requirements for authority and have plenty of time, you can choose UL. UL costs are high and the certification cycle is long.
CSA - a certification mainly based in Canada and also popular in the United States
If your products are mainly for the Canadian market and you want to be slightly cheaper and faster than UL, you can choose CSA .
MET - the most economical and fastest, comes from an authoritative laboratory, and is also certified by the US market.
If the US buyer does not specify that UL certification is required and wants to compare UL is more economical and faster, and simplifies the application process. You can choose others.