OUR PART # 7277SUR
Tiffen's 7277SUR is a larger format filter accessory - a 72 to 77 Step Up Ring. With this step up ring it will allow you to accomodate 77mm filters, lenes or accessories to a 72mm lens. A step up ring allows you to adapt a filter or lens accessory with smaller thread sizes to lenses with larger thread sizes.
If you need to do the reverse - Tiffen offers a series of step down rings which acheive the oppositve effect (allowing you to mount filters / accessories that are smaller than your larger lens.) Remember - try to avoid using more than a two-size difference step down ring as lens vignetting may occur.