Specification:Total 40pcs, each size 10pcs - Grid : 0.1" (2.54mm)Thickness : 1.6mm(5pcs)Hole diameter : about 1mm - The diameter of 4 large positioning holes: 4mm - Material : FR-4 (glass fiber)All holes are plated through - Both sides are identical Dimension Hole(column x row ...Specification:Total 40pcs, each size 10pcs - Grid : 0.1" (2.54mm)Thickness : 1.6mm(5pcs)Hole diameter : about 1mm - The diameter of 4 large positioning holes: 4mm - Material : FR-4 (glass fiber)All holes are plated through - Both sides are identical Dimension Hole(column x row) Quantity50 x 70mm, 1.97" x 2.76" 24 x 18 1040 x 60mm, 1.57" x 2.36" 20 x 14 1030 x 70mm, 1.18 x 2.76" 24 x 10 1020 x 80mm, 0.79" x 3.15" 28 x 6 10 Package included: 40 x FR-4 double side prototype PCB printed circuit board