1. Easy to use 2. Green indicators are ideal range of water temperature and specific gravity for most salt water / marine aquariums 3. Hydrometer measures specific gravity 4. Need it for raising brine shrimp

1. Easy to use 2. Green indicators are ideal range of water temperature and specific gravity for most salt water / marine aquariums 3. Hydrometer measures specific gravity 4. Need it for raising brine shrimp.

Batteries Required?: No. Is Discontinued By Manufacturer: No. Best Sellers Rank: #139,157 in Pet Supplies. Customer Reviews: 3.7 out of 5 stars 32 ratings 3.7 out of 5 stars. Item model number: D667 UP ?. : B00XAFBXYO. Manufacturer: D667 UP ?. Item Weight: 0.3 ounces. Product Dimensions: 0.8 x 0.8 x 6.2 inches.