Abstract: Embodiments of the present invention are related to tension adjustment for a tension spring in a flex arm. Example embodiments include a tension adjustment mechanism comprising a handle, a collar, and an adjustment nut. The adjustment nut is centrally threaded and engages with a threaded shaft. The adjustment nut is positioned between the collar and the tension spring of the flex arm. The collar surrounds the shaft and comprises at least one pin that protrudes toward the adjustment nut. The adjustment nut comprises a plurality of radial slots each separately configured to receive a pin. The handle is connected to the collar and configured to rotate the collar to displace the adjustment nut along the shaft. The handle may be further configured to disengage the pin with a radial slot, rotate to align the pin with a different radial slot, and engage the pin with the newly aligned radial slot.