Tokina 46mm-37mm Step-Down Metal Filter Converter Adapter Ring (Lens (46mm) to Filter(37mm)) New
Lens to Fit = 46 mm ( Male Threads = 46 mm )
Filter to Fit = 37 mm ( Female Threads = 37 mm )
This Stepping Ring enables a filter with an attachment ( 37mm Filter / Tube Adapter / Lens Hood / Lens Cap ) size of 37mm to be used with a lens of 46mm.
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.
Still confused email us to clear it up further and also look at second picture that will help you understand.
We do combine S&H charges.