Description: brand new and high quality Features: Made of high-quality material, durable, firm and stable for us to use. The radiator, also known as the passive speaker, is used to replace the inverter. It has low frequency diving depth, faster speed sense, and low wind noise. So it's a good choice for friends who like to dive deep, but have higher requirements for speed to make subwoofer with radiation basin. Three sizes optional. Easy and convenient to use. Attention: it is not a speaker, no magnet, it can make sound independently. Passive Radiator only, other accessories demo in the picture is not included! Specifications: Item Type: Passive Radiator Material: Plastic=Metal Size: (Optional) 5 inch: outer diameter: 147mm/5.7in, opening hole: 132mm5.1in, diagonal twisting hole spacing: 138mm/5.4in 6.5 inch: outer diameter: 178mm/7in, opening hole: 160mm/6.2in, diagonal twisting hole spacing: 168mm/6.6in 8 inch: outer diameter: 217mm/8.5in, opening hole: 198mm/7.7in, diagonal twisting hole spacing: 208mm/8.1in Color: Black Quantity: 1 Pair Note: Transition: 1cm=10mm=0.39inch Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Includes: 1 Pair x Passive Radiator