These thermometers are useful for determining the highest temperature attained in locations where it is inconvenient or impossible to measure the temperature with a conventional indicating thermometer. Designed with a constriction in the mercury column, these thermometers with display and retain the highest temperature obtained until reset. These units are with a severely restricted capillary to resist vibration and are commonly used in service such as oil well logging and geothermal exploration.

Note: Cannot be reset manually, requires a centrifuge to reset.