eModernDecor Over Mount Installation 16 in. x 28 in. ABS Single Shelf Bathroom Recessed Shower Niche for Shampoo, Toiletry Storage SHC-R-1628 - The Home Depot
VEVOR Shower Niche Stainless Steel, 12'' x 24'' x 4'', Wall-inserted Niche Recessed, Easy to Install, Recessed Shower Shelf Modern and Elegant, Soap Niche Polished Finish for Shower/Bathroom | VEVOR US
Rethinking the Shower Niche (& Why I Think The Ledge Is "Next")
Uni-Green Shower Niche Ready for Tile Flapped Over Designed Shower Shelf Insert 16X28 (UGRN1628) - Amazon.com
DIY Renovation Project: How To Build a Recessed Shower Shelf | Apartment Therapy