6" diameter x 1" thick plastic scintillation detector, sensitivity: typically 2000 CPM/Micro R/HR, meter dial 0-1 Micro-R/HR, multipliers: x1, x10, x100, x1000, alarm: a fixed alarm point can be set or a quick deviation alarm, built in unimorph speaker with on/off switch, uses two "D" cell batteries, weight 8.5 lbs.