Tier 1: This bundle starts you off with the essentials to get you going and keep you safe. Tier 2: This adds necessary items such as a sling, carry case and extra mag to get you out in the field at your local skirmish site. Tier 3: Contains extra bits and pieces such as a dot sight and target so you can practice at home and hone in your skills.Zero One Airsoft, Airsoft, Air Soft, Dorset, Hampshire, softair, , 01, Airsoft, Ar-15, Ar15, Automatic, Bb Gun, Beginner, Combat Machine, Electric, Gun, M4, One, Pellet, Rifle, Softair, Upgraded, Value, Zero, Zero One, Zeroone, Zoa, , ZO, AEG, CM16, Raider, Starter, Pack, Tier, 1, Bundle