1. Correct seat height for both swivel and non swivel glider 2. Maximum strength, stability, side-to-side movement and torque control. 3. All Metal to the floor mechanisms are interchangeable in the same frame 4. Available in -1, -2, -3 etc. seat widths. 5. A cable/lever, outside handle, inside handle and "D" ring can be used for release. 6. Application is for chairs, loveseats, and separated sofas.