Durite gravity ball antifreeze hydrometer.
Gravity ball for mixtures of ethylene glycol only, functioning with less than 5cc of coolant, gives a simple and quick check of anti-freeze content and protection.
- No balls floating: less than 15 percent AF unprotected.
- 1 Ball floating: between 15-20 percent AF protected to -7 degree centigrade.
- 2 Balls floating: between 20-30 percent AF protected to -10 degree centigrade.
- 3 Balls floating: between 30-40 percent AF protected to -15 degree centigrade.
- 4 Balls floating: between 40-50 percent AF protected to -25 degree centigrade.
- 5 Balls floating: higher than, less than 50 percent AF protected to -36 degree centigrade.
Percentage AF and protection calculated at 15 degree centigrade.