New ergonomic design. The M4 & M4E are compact general purpose survey
meters capable of detecting alpha, beta, gamma, and x-rays over 3 selectable ranges.
A red count light flashes and a beep sounds with each event detected.
Monitor 4: Halogen-quenched uncompensated GM tube
Monitor 4EC: Halogen-quenched GM tube, energy compensated sidewall 2mm thin filter.
Both have: Thin mica window 1.5-2.0 mg/cm2 thick. Effective diameter of window is 9.1mm (0.36 inch)
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