Acoustics Model FLS vibration isolators consist of free-standing, large diameter, laterally stable steel springs assembled into welded steel housing assemblies fabricated to limit vertical movement of the isolated equipment if equipment loads are reduced, or if the equipment is subjected to large vertical external forces. The housings also provide a constant free and operating height to facilitate installation. Spring elements are complete with internal noise isolation pads and have an adjusting and leveling bolt as a part of the top load plate assembly. Springs are polyester powder coated, with a 1000-hour salt spray rating per ASTM B-117. Holes are provided in all isolators for bolting to the structure and to the supported equipment. The isolator can be welded to the structure as well. To assure stability, the springs have lateral spring stiffness greater than 1.2 times the rated vertical stiffness, and are designed to provide a minimum of 50% overload capacity. FLS Springs are available with deflections to 4" (102 mm) and with load capacities to 23,200 lbs. (10,524 kg) as standard products. Custom isolators with higher deflection and greater load capabilities are available. Acoustics Model FLS spring isolators are recommended for the isolation of vibration producing equipment carrying a large fluid load which may be drained, such as boilers, cooling towers and chillers, and for the isolation of outdoor components such as cooling towers, air-cooled condensers, etc., where wind loads are minimal.