100% All Natural Lava Rock Mix. No Dyes! Consists of 3/8 inch pieces (ranging from 1/16 inch to 3/4) Better drainage Right amount of heat retention Better aeration Perfect water retention *This product comes new, unused and unwashed as received direct. Total 4 Quarts (approximately +6 lbs) Shipped the same day of payment with USPS Priority Mail + Tracking included. Customer satisfaction guaranteed. Free local delivery.