Measuring the percent by volume of isopropyl alcohol, these hydrometers are offered in two ranges, 0 to 50% or 50 to 100%.
Note: Hydrometers should be stored in a clean, dry, safe place, and should not be subjected to extreme temperatures.
| Thomas No./ Mfr. No. | Length | Divisions | Range | Accuracy |
| 1212Q01/ B61809-4000 | 260mm (10.2") | 1% | 0/50% | ±1% by vol |
| 1212Q02/ B61809-4100 | 285mm (11.2") | 1% | 50/100% | ±1% by vol |
