Features: 20mm black vibrating diaphragm delivers excellent high fidelity sound quality, brings you wonderful auditory feast. The speaker uses NdFeB(neodymium iron boron) magnet drive (magnetic is 10 times of ordinary black magnetic). Toothed aluminum heat sink mounted on the magnet to enhance the ability to withstand high power! High quality ABS frosted panel, beautiful, anti-aging and heat resistant. Suitable for HI-FI speakers, multimedia speakers, surround speakers, teaching speakers, public address speakers, etc. Specification: Item Type: Speaker Material: NdFeB Magnet + Silk Diaphragm + Aluminum Heat Sink + ABS Frosted Panel Impedance: 6Ω Power: 30W Diameter: 52mm/2in Height: 23mm/0.9in Diagonal Hole Distance: 44mm/1.7in Opening Hole Diameter: 34mm/1.3in Package List: 2 x Speaker Note: 1. Due to the difference between monitors and light effects, the pictures may not reflect the actual color of the item. 2. Please allow slight error due to manual measurement. Thanks for your understanding.