JAM Paper & Envelope #4 Coin Envelopes are great to store small items. From cash, to deposit slips, checks, receipts, and random buttons you may find underneath your bed, keeping your valuable items in a safe place has never been easier. Whether you choose a clean white or classic manila look, our durable and professional open end envelopes have your back. These envelopes are made from smooth 28 lb. paper. They are open ended, have a peel and seal closure.