Major Fitness Lever Arms Jammer Arms for Power RacksJammer Arms for Power Racks Level up your rack with jammer arms for power racksthe fastest way to add explosive presses, rows, and lower body patterns without buying a separate machine. These lever arms run bilateral or unilateral: train each side independently for balance and rehab work, or lock them together for big compound moves. Loading is flexibleweight plates for straightforward strength work or connect to your cable system for constant tension