Place these compact, portable pressure recorders anywhere a written record of pressure is needed. The durable Velox PBT NEMA 4X-rated case protects against corrosion, windblown dust and rain, splashing water, and hose-directed water. Recorders are ideal for investigating and monitoring systems for gas, steam, and water leaks; documenting system pressure at water treatment/ purification facilities; and measuring flow of water wells. Unique door closure ensures weather resistance. Recorder operates for up to one year on a single AA battery. On/off switch provides battery savings. Battery holder is located inside the door for easy battery changes. Note: These pressure recorders are not suitable for monitoring ammonia, acids, or other corrosive substances.