The following is not electrical advice. Please contact a qualified electrician if you have questions!

People often ask what the difference is between SPT1 and SPT2 wire. The main differences would be the thickness of the wire/insulation and the amount of amperage it can handle.

Generally speaking, SPT1 wire can handle 7amps, while SPT2 can handle 10amps. The thickness of the insulation will come into play as well for weather related purposes.