DUAL CHANNEL NOISE GATE WITH ADJUSTABLE SENSITIVITY AND FACTORY SET THRESHOLD. ATTENUATES GAIN AT LOW PROGRAM MATERIAL VOLUME TO INCREASE SIGNAL TO NOISE RATIO BY 10DB. GREAT FOR REDUCING HISS AND NOISE DURING QUIET MUSIC PASSAGES AND SPACES BETWEEN SONGS. INCREASES DYNAMIC RANGE ALSO. SMOOTHER TRANSITION THAN OTHER TYPES OF NOISE GATES. 4 CHANNEL MODEL IS SHOWN IN PICTURE. INCLUDES INSTRUCTIONS AND POWER HARNESS. AS WITH ALL HARRISON LAB PRODUCTS - MADE IN USA