Used in good working condition. It's heavy so pickup only in Westmont, IL is being offered (near Chicago). This vintage amp is a hard to find item. Not much about it online. One rickenbacker info page stated: RG180
It's the one you see on RIC's Schematics page, one of the last models built in 1988/89, just before John Hall pulled the plug on Rickenbacker's amplifier operations.
The preamplifier was the same on the RG90.