The UD 5 should be added to your arsenal if you are serious about building superior upper body strength. The compact design of the UD 5 still allows for a full 37" wide pull up. The innovative cantilever design has a look about it that sets it apart from all other doorway chin up bars. The rugged design includes super hard powder coating with strategic parts mig welded for that sleek functional profile. Truly a world class ergonomically designed doorway chin up bar. The UD-5 was designed for standard 4" walls and overhead trim that does not exceed 4 " wide.