Based on this product's specifications, here are some alternatives and similar models
Magnetic door/window open sensor bleBox openSensor black 2m — wireless contact sensor with 2 m cable
Summary description:
bleBox openSensor (black, 2 m) is a magnetic contact open sensor for doors and windows. It detects opening/closing via a wired magnetic contact with a 2 m cable for flexible mounting. Designed for integration with bleBox systems and smart home setups, it provides status monitoring, event detection and can be used for security, automation triggers and remote notifications.