The waterproof pHep® 4 and pHep® 5 pH testers easily and accurately measure pH on the spot. These waterproof pH testers have a dual-level LCD that displays pH and temperature (°C or °F). At startup, pHep® performs a self check then displays the remaining battery level to assure proper working condition. These testers also feature a stability indicator and hold feature to prompt the user when to take the reading & freeze the display for easy and accurate recording. These new pH/Temperature meters have a stainless steel temperature probe for faster and more precise temperature measurement and auto-compensation. 1 or 2 point calibration is made simple with automatic recognition of both standard and NIST buffer sets. These new pHep® pH electrodes are designed with an extendable reference junction, and when the electrode finally is exhausted simply insert a new electrode cartridge! pHep® is supplied complete with 4 x 1.5 V batteries, BS4 72-6087 pH electrode and BS4 72-6088 electrode replacement tool. pHep® 4 has the most common pH range of 0.0 to 14.0 pH, while pHep® 5 has a more precise pH range of 0.00 to 14.00 pH.