The BCW Storage Box is the highest quality, most competitively priced cardboard storage box on the market today. They are constructed of white corrugated paper and have a 200 lb. test strength. Use this box to store and protect collectible trading cards like: baseball cards, basketball cards, football cards, Magic The Gathering, Yu-Gi-Oh, Pokemon, and others. EASY TO FOLD & WON'T OPEN DURING SHIPMENT- These one-piece shipping mailers can be assembled in seconds, and no tape, glue, or staples are needed. With special design of LOCK on the opening, the small white mailing box will be always locked during shipment and won't open; Instructions are included; BOX SIZE - The INNER size of these white mailing boxes are 4x4x4'', The outer size is 4.4 x 4.2 x 4.2 inch; CRUSH PROOF - made of 200#/ECT-32-E white single wall corrugated, the Crush resistant mailers fold to provide double walls of protection on both sides, make it super strong yet light-weight to save on postage; PERFECT FOR - These white mailers are perfect for shipping packing mailing or storing small fragile items, like candles, mugs, small soap, and any other retail shipping or little gifts, multifunctional & durable recycled; NO-ASK RETURN POLICY - If for any reason, you don't absolutely like the white mailing boxes,just return it, and we'll refund every penny (or replace it, if there is a problem).