5-Step Calibration Block with imperial and metric markings for ultrasonic thickness gauges., Reed Instruments, Mfr#: R9060$235.99+
Multi-Gas, Personal Monitor for CO, H2S, O2 and Combustible Gases(LEL), Macurco, Mfr#: AIM-4GAS-100/25/50/18-58L-F$301.99+