Based on this product's specifications, here are some alternatives and similar models
Mounting accessory sera double suction cups for heaters model 21281
Summary description:
sera double suction cups (model 21281) are mounting accessories designed to secure aquarium heaters and similar cylindrical devices to glass surfaces. The pair of suction cups provides stable attachment to aquarium walls, enabling adjustable positioning of heaters for optimal water temperature control. Suitable for use with compatible sera heaters and other aquarium equipment requiring suction mounting.