Type in the height of the lid (the distance from front to back of the lid) and the weight of the lid:
Height (inch): Weight (pounds):
Note: Inch-pounds is found by multiplying one-half the distance from front to back of the lid times the weight of the lid.
For your application of a 36” wide x 20” deep at 9 lbs in weight, I would use a single lifting mechanism with a yellow rated spring which will handle a 65 to 95 inch pound rating as seen here:
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