The Capetsma Salinity Tester is an accurate and easy-to-use hydrometer that is perfect for testing your marine aquarium’s salt level and specific gravity. Made of durable acrylic, this hydrometer is designed with an automatic level function that ensures that the test results are always accurate and consistent. The easy-to-read swing-arm pointer and extra wide stable base provide an accurate test result, while the included salinity and specific gravity scales ensure that the test results are always consistent and reliable.