Aviditi HD18188DW Double Wall Corrugated Box, 18" Length x 18" Width x 8" Height, Kraft (Bundle of 15) Twice the protection of a standard carton. Use when extra stacking strength is needed. Manufactured from heavy-duty 275#/ECT-44 double wall kraft corrugated. These durable boxes can support up to 100 pounds. Cartons are sold in bundle quantities and ship flat to save on storage space and shipping. Made in the USA!