DURABLE VINYL: 'Wheels Must Be Chocked Before Loading Or Unloading' labels are made from conformable reflective vinyl that is laminated for superior protection and has a 7-year outdoor life. EASY INSTALLATION: Material has an aggressive adhesive backing. Just remove the liner and apply the label to any clean surface. Labels stick to flat or curved surfaces and can be used indoors or outdoors. 3M AUTHORIZED: Made from Certified 3M components: inks, laminate and films, these 3M engineer grade reflective labels shine brilliantly at night. Spot them easily with a flashlight or headlight, or at night. OSHA COMPLIANCE: Safeguard your workplace from accidents and liabilities by placing our high-quality signs that follow OSHA regulations. These are universally recognizable and encourage safe work practices. PACK CONTENTS: One 7 x 10 inch black and yellow label.