The top unit is a TUFF and the bottom is an Elite.
Remember that Elite went out of business several months ago and has recently begun a campaign to resurrect itself through the Delco/Simpson name.
A pressure washer dealer on Long Island bought that portion from Alto and have begun (or soon will) building pressure washers again in the old Elite facility in AR using amny of the same people that closed it earlier. Not casting stones nor aspersions merely stating facts.
The RK series for the last while has been built by Ramteq (I believe) who also supply Karcher with skids and gas-fired units.
Just an FYI.