Features: Upgrades your sound experience with the 120x49mm vibrating plate, featuring customs rubber edges, iron plate weight, and long strokes design for powerful bass reinforcement in speakers (3 4inch compatibility) without glues installation. precisions engineered with high densities wood housing, rubber suspension, and screw mountable iron brackets to minimize distortion while delivering 90dB sensitivity across 20Hz 200Hz frequency ranges for clear low end reproduction. for audiophiles, speakers builders, and home theater enthusiasts seeking professional bass enhancement for customs sound projects or existing sound systems upgrades. Perfectly integrates into home entertainment setups, gaming stations, or music production environments where deeply, resonant low frequencies elevates movie soundtracks, game effects, and instrumentals separation. Outperforms standard bass driver through optimized acoustics chamber geometry and magnetic components, ensuring airtights screw secured installation for vibrationfree operations in 120x49mm dimensions. Specifications: Materials: plastic Color: black Size: 120x49mm Package Includes: 1PC Assist Vibrating Plate note: Please allow 0-1cm error due to manual measurement. make sure you not mind before bid. Due to the differences between different monitors, the Pictures may not reflect the actual of the item.