Amazon.com: Newks 24 Pieces Lens Filters Adapter Ring Set, Camera Lens Filter Metal Rings Kit,Includes 12pcs Step Up Ring Set & 12pcs Step Down Ring Set,for 26/30/37/43/49/52/55/58/62/67/72/77 to 82mm : Automotive
The Wisdom of Step-Up and Step-Down Rings | B&H eXplora
What are step up and step down rings? | Discover Digital Photography
H&Y Revoring review / The End of Step-Up Rings? - Todd Dominey