Its a great way to convince a sponsor to buy the clocks for your sports group! You can easily slip a 12-1/4" high by 15-1/2" wide sponsorship or advertising card into the back frame of the clock display to acknowledge your sponsor! Simply loosen the screws on the 'plug-side', remove the side frame, slip in an advertising card over the instructions card (your user guide will remain safe within the clock), put the side frame back on and tighten the screws. When the clocks are hanging from the arena glass or clipped together for transport, the sponsor cards face out!