The Selenium DT150 is a car tweeter called a "Super Tweeter" because of its extended frequency response range. This Selenium 4x4-inch car speaker uses a square horn design and incorporates a number of features for high power output and clear sound, including a 1-inch phenolic dome compression driver. The Selenium 4x4-inch car speaker offers an RMS power handling at 75 watts and peak power handling of 105 watts. The impedance for this car tweeter is 8 Ohms and the sensitivity is 107 dB at 1 watt/1 m, allowing it to efficiently translate power into volume. The frequency response of the Selenium DT150 is between 1500 Hz and 18 kHz. This Selenium 4x4-inch car speaker is designed to be small and compact, ideally suited for two- or three-way car speaker systems. Measuring 4 inches in height, 4 inches in width, and 4.75 inches in depth, this non-enclosed speaker requires a cutout size of 3.38 inches, fitting into the back dash or the door of a car.