Moreover, the base can be filled with water (50 kg) or sand (100 kg) for extra stability. Upgraded Shock-Absorbing System: Our boxing bag is equipped with 4 springs to deliver 15-45° fast rebound, 2 PVC absorbers to achieve 360° shock absorption. The springs can also be removed for less vibration when you want to do high-intensity strength training. Plus, the mute cotton creates a lower noise environment while boxing, punching, kicking and hitting. Specifications: Color: Black Material: Stainless Steel, Pearl Cotton, Fabric, PU Leather, ABS Overall Dimensions: 50 x 50 x 175 cm (L x W x H) Weight of Filled Water: 50 kg Weight of Filled Sand: 100 kg Net Weight: 16 kg Package Includes: Box 1: Punching Bag Box 2: 12OZ Boxing Gloves; Accessories; Manual.