we are a professional company handling in the natural slate. Our product have confirmed the BS680, EN12326 standard. Our sizes: 600x300, 600x450, 500x250, 500x375, 400x250, 400x200, 400x300 Thickness: 5-7/6-7/6-8mmColor: Grey, Dark Grey, Grey Black.BlackPacking: in wooden cratesDelivery time: about 15-25 days upon getting your order.Minimum Quantity order: One 1x20'fcl" Roofing slate