Accessories for Hammond 1593 Series Instrument Cases – Hammond 1593PPCB, ProtoBoard printed circuit board, high quality FR4 glass epoxy board, lead free, etched copper PCB (single sided) with a flux coating for easy soldering, for use with Hammond 1593PTBU enclosures. Hammond 1593PPCB Protoboard PCB for 30-1850 1593PTBU