I ordered this for my Hammer Strength plate-loaded tibia dorsiflexion device so I can comfortably use it bilaterally while seated, and it works perfectly. If you sit on a bench with the HS tibia dorsiflexion positioned in front of you so your shins are at a 45 degree angle and your feet and legs are parallel to each other, the resistance curve is nearly perfect. This works much better than using it unilaterally while standing.