These Spontaneously Combustible Preprinted 4-Digit Placards are in stock and ready to ship. We make it our business to stock the Hazard Class 4 placards with the preprinted UN Number you need to meet the requirements of 49 CFR 172.500 for domestic and international shipments of hazardous materials by highway, rail and water. Our Hazard Class 4, Spontaneously Combustible 4-Digit Placards measure 273mm x 273mm. Sold in packs of 25.