Post items with dependable and flexible protection using polythene mailing bags lightweight polythene provides a dependable waterproof seal for fragile items use the peel and seal flap to keep items securely contained just remove the protective tape and press down to keep everything neatly in place and because the polythene construction is so light it helps cut down on postage costs flexible mailing envelopes extra light construction to reduce postal costs flexible polythene protects co