Trace SWI
Stacking kit for stacking two SW inverters. Provides 120/240-vac, 3 wire, and twice the power at 240-vac.

Trace SWI/PAR
Sine-wave paralleling kit. Connects two sine-wave inverters together for twice the power at the same voltage.

 
Trace SWI SW-series stacking kit
$ 45
Trace SWI/PAR SW-series paralleling kit
$ 345