Hiking backpack: The Thule LANDMARK 60L W is ideal for adventure travel and has a detachable accessory pack in a feminine design for maximum carrying comfort. Take day trips with the 20L removable accessory pack with space for a 15" MacBook® , and a breathable back panel and a hidden CashStash pocket for money and personal items. In the CashStash compartment, hidden under the SafeZone, you can store money and cash to protect it from pickpockets. It is designed so that it can be used as hand luggage with the detachable additional backpack. The whistle integrated into the chest strap of the main backpack can be easily moved to the auxiliary backpack for increased safety.