Amazon.com: Aviditi T161640OUTER Telescoping Corrugated Cardboard Box 16 1/2" L x 16 1/2" W x 40" H, Kraft, For Shipping, Packing and Moving (Pack of 10) : Office Products
48 X 40 X 36 - 68" 200# 2 Piece Telescoping Box
Custom Telescoping Boxes | PakFactory
Custom Telescoping Boxes - from Cactus Containers
Made in USA - 16-1/2" Wide x 16-1/2" Long x 40" High Rectangle Telescoping Box - 39545801 - MSC Industrial Supply
Made in USA - 20" Wide x 20" Long x 40" High Rectangle Telescoping Box - 39556949 - MSC Industrial Supply