Overseals can be applied quickly with a mallet or even faster with our easy-to-use paint can closer, # 7855. These overseals have passed Internal Pressure Tests of 95 kPa conducted in accordance with Title 49 Code of Federal Regulations, Part 173.27 when used with 1/2 Pint. They also meet UPS and US Post Office requirements. The overseals are not reusable, but are recyclable. Food Grade.