Yes, it will work with the Sun Joe SPX3000, but you may need adapters for the fittings, and you should use moderate pressure settings for safe operation.
The wand connects to the harness using a support hook/clip system: the wand has a mounting bracket that locks into a holder on the shoulder harness, so the harness carries the weight while the wand slides/adjusts freely.
Yes, it can connect to standard pressure washers. The product description states that it is equipped with a 3/8 inch quick plug inlet and adapters, allowing it to work with most pressure washers on the market.
