The Sparrows ULTRA decoder is designed to decipher the combination of multi wheeled locks. By placing the Sparrows ULTRA on the axle that runs though the wheels inside the lock the operator can feel for changes in the features of the axle. Flat spots or grooves on the axle can be felt by the Ultra Decoder as the operator spins the wheels. These flat spots or grooves will reveal the locks combination. By using the decoder on the axle beside each wheel the operator can line up all the flat spots or grooves to the same position. When this is done the combination will be set. The final step is to move combination into the correct position. Simply roll each wheel down one position and test the lock to open. Repeat this process until it does open. The ULTRA Decoder is made from thin high test steel with a solid steel handle covered in a thermo plastic coating.