This set of counterweights attaches to the rear of the primary mirror box with included nut and washer. Simply remove the rubber stopper and insert shaft through and attach with nut and washer. Includes 2 - 2.5 lb counterweights.

Specifications 

• Item Number: DOB-CW
  
• Includes: Counterweight Shaft with nut and washer
• Weights Included: 2 - 2.5 lb weights