This is a DU-BRO 1.20-1.50 4-stroke and 1.20-1.80 2-cycle Engine Vibration Reducing Motor Mount. Made of aluminum Two-piece design allows for many different engine sizes to be mounted Effectively reduces vibration/harmonics, greatly reducing airframe & component fatigue Simple & easy to install Specially designed elastomerics (rubber mounting grommets) to absorb vibration Helps in airframe noise reduction One left half of mount Eight elastomerics One right half of mount Four mounting screws Eight spools Four blind nuts Length of each arm: 3-1/4" Overall length of mount: 4" ir/jl &