The MOSFET Plug is a small board containing two high-power MOSFETs for switching loads at up to 5A @ 50V (this will require an extra heatsink).
A maximum current of 1-3 amps should work fine, for use without heatsink. Just keep in mind that MOSFETs can generate a few watts of heat when used continuously at 2A or more. You can tie the MOSFETs in parallel for larger currents (heatsink required).
This plug was designed for driving LED strips, but other loads can be driven as well. With two MOSFET Plugs, there are 4 individually controllable switches – to drive an RGB strip and a white strip, for example.
The Kit version comes with all the parts needed, including a high-power terminal block with individually detachable connectors and a 6-pin right-angle header.
The PCB only variant contains just the board for the MOSFET Plug. No parts, no headers.