MSSH Series Isolators, are the MS Series Isolators reinforced for high seismic load conditions. MSSH Isolators are designed for the maximum seismic design categories in the United States. MSSH Series Isolators, combine our open spring isolators within a rugged welded seismically rated steel housing. To minimize, the code required seismic loads on the isolated equipment. The housing is designed to limit equipment motion to ¼" in horizontal directions due to wind or seismic loads.

The MSSH Series incorporates an external adjustment bolt that also acts as a single point attachment to the equipment. The top housing incorporates seismic restraint bolts that pass through the lower housing and are protected in all directions by an elastomeric bushing. Combined, the restraint bolts and bushings act as the internal snubbing devices for the isolator. To achieve accurate installation heights, VMC Group has incorporated an installation spacer between the lower and upper housing. After the equipment is installed and the isolators are properly adjusted, there will be no difference between the installed and operating heights.

Mechanical equipment is attached to the MSSH style product by using the adjustment bolt of the isolator to fasten to the equipment's designated mounting locations. Low frequency T-Series steel springs are located within the housing and are seated in an elastomeric acoustical cup that provides high frequency attenuation and eliminates metal-to-metal contact. The spring and cup design allows for easy replacement or changing of springs when required and all springs are color-coded for ease of identification in the field. The lower housing incorporates an oversized base plate that spreads the anchor bolt over a wider area - this is specifically designed to increase seismic restraint capability. As an additional benefit, ease of installation is also achieved by allowing easy access to the anchor bolts. These isolators are designed for installations in either concrete or steel and the base plates are pre-drilled with mounting holes to accommodate attachment to either. MSSH Series Isolators are available with 1" through  5" deflection springs. Each style of mount has a load range from 50 lbs. to 19,500 lbs.

Features & Benefits

  • Rugged steel housing serves as blocking during equipment erection
  • Housing offers no difference in elevation between installed and operating height
  • Installation spacer ensures accurate installation height and adjustment
  • Single point attachment
  • External adjustments for single point installations with interchangeable springs
  • Attachment/adjustment bolt of the isolator fastens to the equipment’s designated mounting locations
  • Housings are identical in height within each series
  • Easily accessible bolt holes permit simplified installation
  • Elastomeric acoustical cup eliminates high frequency vibrations
  • Color-coded springs permit ease of identification of load capacity
  • For use in high seismic and wind applications


  • HVAC equipment
  • Air handling units
  • Condensing units
  • Chillers
  • Pumps
  • Engine gensets
  • High seismic loads




The engineers we employ hold the highest industry-recognized credentials in structural analysis, elastomer development and system dynamics.


We are the first ISO accredited PCA ISO-17065, third-party certification body for special seismic certification of non-structural building components and their mounting configurations by the ICC’s International Accreditation Service.

Test & Measurement

We are the only ISO 17025:2005 Accredited Seismic Simulation Test Laboratory with a triaxial shake table owned and operated by California licensed Structural engineers.

Testing Services Update
DCL now offers Nuclear Qualification and Testing services.

In partnership with Greenberry Industrial, we now offer testing services that meet the requirements of ASME NQA-1.

Call for more information.