Onyx Gravel poly bags are made up of 15mm - 20mm buff marble gravel pieces with angular edges. Ideal for driveways, rockeries and boarders. Features: Size: 15mm -20mm Colour: Buff Shape: Angular Rock Type: Marble Fish Friendly: No Supplied Washed: Yes Lime Free: No Recycled: No Available in 20kg Poly bags or 850kg Bulk bag.