Standard Chime Movement with Built-in Speaker & Pendulum (2 3/4 in. Bob. Dials up to 5/8 in. thick) Chime synchronization knob Step second motion (second hands are optional) 3 year replacement guarantee Includes a 16" adjustable pendulum with a choice of a 2-1/8", 2-3/4" or a 3-1/2" pendulum bob.