Features: The 3inch widebands speaker delivers high fidelitys audios with its 13core copper voice coils and 4Ω impedance, optimized for seamlessly compatibility with 15W Bluetooth-compatible amplifiers in compactly sound systems. Featuring aluminum frame, full paper diaphragm, and external magnetic structure, this speaker ensures uniform magnetic flux distribution while minimizing high frequency distortions through its airtights circular cavity design. Perfect for DIY audios enthusiasts and home theater upgraders seekings professional components to customize bookshelfs speakers or portable sound equipment. Enhances acoustics performances in confined space like desktop multimedia setups, radio restorations, and compactly home studio monitors installations. Engineered with precise measured 98mm outer diameter and 61.8mm mounting hole for effortless integration into standard speaker enclosures while maintaining optimal phase coherences. Specifications: Diaphragm Material: Paper Diameter:Approx.69MM/2.72inch Rate power:15W Rate impedances:4Ohm Magnetic circuit form: external magnetic type Voice coils: 13cores Frequency response: 1100HZ-20KHZ Sensitivity:90±2DB Harmonics distortions: 5% Frequency characteristics: high frequency (treble) Package Includes: 1pc 3inch note: Please allow 1-10mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual item color.