The heart of the KOOLTRAK™ system is the KOOLTRAK™ temperature logger. In a waterproof stainless steel can is hardly bigger than a dime, and contains a complete recording system with a microcomputer, memory, communications circuitry, temperature sensor, clock, and lithium battery power supply. The wide temperature range, long recording time, and 10-year life make this fantastic product the first choice for compact, low-cost temperature recording. Price Discounts Range: 50 - 100 = $44.81 Range: 100+ = $42.45