37-82 and 82-37 mm 9pcs set Universal aluminum Step Up Step Down Adapter Ring Camera Lens Ring for camera filter

Adapter ring is suitable for filters, close-up lenses and other attachments to lenses with different filter thread sizes.
Step up / down rings, also know as adapter rings, allow you to use filters and accessories that are not the same size as your cameras lens.
The first number is always the lens thread size, the second number is the filter size of the accessory. If the first number is bigger, it's a step-down ring. If the first number is smaller, it's a step-up ring.