The CHC/CHK/CHT-100 crystal holders are designed to be dipped into a liquid. The crystal holders provide users with a rugged and easy to use quartz crystal housing for QCM experiments. Seamless construction, a choice of three chemically resistant materials and an o-ring sealed crystal allow the holders to be used in a wide variety of gases and liquids over a broad temperature range. A removable retainer permits easy crystal replacement. The compact holders are designed to use 1 inch dimater sensor crystals.