Mega microtrak fr4 positive photoresist copper clad printed circuit board pcb mega electronics 03 5151 450 x 300mm double sided copper clad fibreglass pcb laminate photoetch board coated with a high resolution photo resistmicrotrak laminates consist of fr4 epoxy glass laminate sheets dip coated with a positive working photo resist the photo resist contains a dye that provides a good contrast against the copper and allows boards to be easily inspected at the developing stage boards are pro