The Bose 201 IV is a bookshelf speaker system produced by Bose Corporation. It is a 2-way speaker system with one 6.5-inch woofer and one 2-inch tweeter. The speakers have a frequency response range of 10Hz - 100kHz and a power handling capacity of 120 watts. They feature a compact design and are suitable for use in small to medium-sized rooms. The Bose 201 IV is known for its balanced sound and wide dispersion.