The PreSonus Eris E3.5 is a pair of 3.5 inch 2-way 25W nearfield monitors designed to provide a compact sonic reference system for musicians, producers, and audio engineers in home setups, project studios, and commercial facilities. Each monitor produces a frequency response of 80 Hz to 20 kHz via a 3.5 inch Kevlar woofer and a 1 inch silk dome tweeter powered by a 25W class AB amplifier.