Proma fr4 epoxy resin boards positive cu 35 m 100 250mm l proma 108020 1016 the proma fr4 epoxy resin board positive cu 35 m single sided 05 x 100 x 160mm has been manufactured with a photo coated base material positive and boasts a 05mm thickness this value board is ideal for constructing fixings chassis facings etc and can be easily worked using normal tools proma 108020 1016 fr4 epoxy resin board positive cu 35 m 1 sided 05x100x160mm