No. 1 Coin and Small Parts Envelopes make the perfect envelopes for small items in your home or office. 2-1/4" x 3-1/2" size is ideal for coins, seeds, medication or any small parts. Heavyweight, 28 lb. brown Kraft stock ensures contents stay secure during storage and handling. Fully gummed flap provides a strong seal to fully contain items.No. 1 Coin and Small Parts Envelopes make the perfect envelopes for small items in your home or office. 2-1/4" x 3-1/2" size is ideal for coins, seeds, medication or any small parts. Heavyweight, 28 lb. brown Kraft stock ensures contents stay secure during storage and handling. Fully gummed flap provides a strong seal to fully contain items.