... direct, Quarry owner 2). Ten years experience. 3). Good packing Natural stone stair treads:1.Color: grey, white, black, yellow, ... , as requested, Thickness tolerance: +/-1mm, +/-1.5cm or +/-2mm, The quality requirements must be comfirmed by customer. Welcome to inquiry ... our company:Slab, tiles, countertop, paving stone, curbstone, monument, etc Natural stone stair treads with low price and A grade