The standard PRO PAC includes a roomy mute compartment (dimensions 18" x 4.25" x 5.25") and accommodates 2 mouthpieces. It comes with a shoulder strap – or you can choose to purchase our optional Padded Backpack Strap (model# BPSTRAP). # Velcro 'quick-lock' closure # Backpackable (Backpack strap sold separately) # Lightweight shock absorbing frame # Soft velvoa lining # Accessory compartment # Roomy exterior pocket # Built-in organizer to hold pens, keys, and small accessories # Includes padded shoulder strap and ID tag # 1680 gauge ballistic nylon exterior; water and abrasion resistant