I can start with similarities:

- torsion spring grippers develop crushing grip strength

- because of the physical properties of torsion spring grippers (batch of materials used for the spring, seasoning, etc.) the tension varies from batch to batch and over time

- the lbs rating is just an estimation, but can be measured and similarities can be drawn and ratings can be determined.

- advanced training techniques for grippers; overcrushes, btr, strap holds, inverted closes, finger specific training and so on...

Now, to answer your question:

In my experience, the simple answer is quality. Ironmind has the best quality control and product in the business. Next in line are Warren Tetting's Beefbuilders.

,
Jim Smith