A retaining device for retaining a shower caddy or other item on a shower arm or other elongated member includes a clip structure for partially surrounding the shower arm or elongated member and having retaining arms extending therefrom and a plastic sleeve structure having receptacles for receiving the retaining arms to hold the sleeve structure on the clip structure, and a shower-arm engaging portion or elongated member engaging portion for engaging the shower arm or elongated member to render the shower caddy or other item immobile on the shower arm or elongated member.