Unlike prior Sun systems there was no rack-optimized direct counterpart to the SS20 the "SPARCServer 20" was a super rare badging for like, workgroup servers

Unlike prior Sun systems there was no rack-optimized direct counterpart to the SS20 the "SPARCServer 20" was a super rare badging for like, workgroup servers the big rackmount units for the sun4m era were still VME systems: 4/670, 4/690, etc