Box Sealing Tapes. 100% polypropylene film with hot-melt adhesive. Flexible, waterproof, slit-, burst- and stretch-resistant. UPS and Parcel Post Approved. General-Purpose Tape. Good holding power, economical. For sealing cartons to 25 lbs. 1.85 mils thick, 28-lb. tensile (bursting) strength. All rolls are 2" wide (48mm), with a 3" core. 6 rolls per pack. 55 Yards (50m) Long. Clear.