The Autonics PRD12-4DN2 is designed for flush installation with a sensing side diameter of Ø12 mm and a sensing distance of 4 mm. It offers a hysteresis of up to 10% of the sensing distance and is tuned for a standard sensing target of 12 × 12 × 1 mm iron. The unit operates from 12 to 24 VDC with ripple tolerance and 10 to 30 VDC, drawing up to 10 mA, and provides a control output of up to 200 mA with a residual voltage of up to 1.5 V. A red operation LED indicates status. It includes surge protection, short/overcurrent protection, and reverse polarity protection, and achieves insulation resistance of at least 50 MΩ at 500 VDC, with a dielectric strength of 1,500 VAC 50/60 Hz for 1 minute. Vibration tolerance is 1.0 mm at 10–55 Hz in X, Y, Z directions for 2 hours, and shock tolerance is 50 G with three shocks per axis. Operating ambient temperature ranges from -25 to 70 °C, with storage from -30 to 80 °C, and humidity between 35 and 95% RH. The device carries IP67 protection and uses a cable connection with a standard black PVC cable. The housing is nickel-plated brass for the sensing side (Ø8 mm) with SUS303 connector case, a nickel-plated iron washer, and sensing side PBT. Packaged weight is approximately 74 g.