Shelly Plus 1 is a 1-channel relay with 16A maximum load and dry contacts. Shelly Plus 2PM is a 2-channel relay with a 10A maximum current per channel and power metering. Shelly Plus 2PM can control bi-directional motors, which makes it suitable for automation and control of roller shutters, blinders, and awnings. Shelly Plus 1 is suitable for garage doors due to the dry contacts.