It's a bath tray! This one in particular. https://www.amazon.com/gp/product/B00WCBC1BG/ref=oh_aui_detailpage_o07_s01?ie=UTF8&psc=1

Here ya go! My bath is against a wall and it still works. This is my parents' bathtub actually - with mine it's against a wall and I have to be kinda careful but it works lol. https://www.amazon.com/gp/product/B00WCBC1BG/ref=oh_aui_detailpage_o07_s01?ie=UTF8&psc=1