These are rare Boston acoustics CR 67 shielded bookshelf audiophile speakers, tested for quality and performance. Universally compatible with a number of audio inputs including bare wire, spade lugs, banana jack, the 6.5" DCD woofer produces high-end RMS power of up to 100 W with an 8-ohm impedance. Available in the sleek rectangular shape with a black finish, these compact speakers make a great addition to your entertainment system.