Based on this product's specifications, here are some alternatives and similar models
Sacrificial Magnesium Anode NOVA TEC NT-S 200 mm with M6x10 mm Thread
Summary description:
Sacrificial magnesium anode NOVA TEC NT-S, 200 mm length with M6x10 mm threaded connection. Designed to provide cathodic protection for steel and metal components in water-containing systems, tanks or marine applications. Easy to install on compatible fittings; reduces corrosion by preferentially corroding itself, extending service life of protected equipment.