Helps protect your cargo against tampering and theft. Tin-plated steel with information embossed, measures 3/8"w x 8-3/4"l. Break strength: less than 500 lbs of force to disengage. Stock seal numbers are embossed with "Keller Seals" and numbered consecutively with our choice of starting numbers. Can be used for trailer doors, rail cars, and storage equipment and more. *Seals must be purchased in increments of 100.