Designed to be tough and resist all impact blake corrugated board envelopes protect your items from damage and ensure that they arrive exactly as they left the corrugated design of the cardboard provides a greater stability to the envelopes and also helps to absorb some of the shock that can come with transit the rip strip opening provides protection against tampering and allows for easy access to your envelopes corrugated board envelopes for secure postage absorbs shock and minimises damag