This innovative design uses tempered float glass as a foundation for each stone, giving it a degree of dimensional stability and strength while ensuring that all the abrasive is usable.
The stones are 210mm × 70mm × 11mm (8 1/4" × 2 3/4" × 7/16") overall with 5mm of usable abrasive thickness, and weigh about 14 oz (400g). The 500x stone is also available with a thicker 10mm abrasive layer (15mm thick overall) for those using this stone regularly to grind bevels; it weighs 19.75 oz (560g). Use with the Shapton stone holder or field holder for a solid base that holds the stone at a good working height.
The GS series has the largest range of grits and will appeal to technical sharpeners who can build a sharpening regimen that meets the needs of any blade. The HR stones are the regular stones; for forge-welded composite steel blades, Shapton recommends the HC-designated 4000x, 6000x and 8000x stones (sold separately) that use a different abrasive agent best suited for those blades.