6 Pc. Hexagon Set 1.5", 2". 2.5", 3", 3.5" and 4" -1/8" Thick-All with Guideline Holes & Seam Allowance 1/8" Thick Clear Acrylic -Set does have seam allowance. Markings are laser engraved for long lasting use. Measurements are from top to bottom from seam allowance lines. Works with our UPC#635231871015 Equilateral Triangle Set