Chest packs, also known as chest rigs or chest harnesses, are wearable gear designed to carry small items or equipment securely across the chest. They typically consist of a harness system with multiple compartments, pockets, or attachment points for organizing and accessing essentials such as keys, wallets, phones, tools, or medical supplies.
Chest packs are commonly used in outdoor activities such as hiking, camping, fishing, and hunting, where individuals need easy access to their gear without hindering their movement. They are also popular among photographers, cyclists, and runners who require quick access to equipment or essentials while on the move.
These packs come in various designs, including minimalist styles with a few pockets for essentials, modular setups with customizable attachments, and more robust options with additional features like hydration bladder compatibility or MOLLE webbing for attaching additional gear. 
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Overall, chest packs provide a convenient and accessible way to carry essentials while keeping your hands free and distributing weight evenly across the torso for comfort during extended wear.