PCB Fabrication Package. Google Mega2560 Arduino Rev. C 2011-03-23 Gerber Files in RS-274-X Format m256_tslk.gbr - Top Silkscreen m256_tpst.gbr - Top Solderpaste (Stencil) m256_tmsk.gbr - Top Soldermask m256_tcmp.gbr - Top Copper m256_bcmp.gbr - Bottom Copper m256_bmsk.gbr - Bottom Soldermask m256_bslk.gbr - Bottom Silkscreen Drill files: m256_drl.drl - Excellon Drill file Fab drawing: m256_fab.pdf Coordinates: m256.mnt - Top SMD coordinates Board dimensions/outline included as zero width trace in silkscreen layer for reference. Board is made from 0.062" FR4 with 1oz copper on all layers. Minimum trace/space is 6/6 mils. NOTE: Board contains 3 plated slots, each slot is marked at the two ends and center with 0.041" drills. Board layers stacked as follows: Top Silkscreen (Black) Top Soldermask (White) Top Copper (1oz) FR4 (62 mil) Bottom Copper (1oz) Bottom Soldermask (White) Bottom Silkscreen (Black) Process the silkscreen layer against the soldermask layer to prevent overlapping silkscreen on the pads through mask openings.