SICK WTB4S-3P5232H Photoelectric sensors. SICK WTB4S-3P5232H is a photoelectric sensors in the W4 family. SICK identifies this exact configuration as manufacturer article 1054864. The official technical record specifies Functional principle: Photoelectric proximity sensor; Functional principle detail: Background suppression; Sensing range max.: 4 mm ... 120 mm 1); Sensing range: 10 mm ... 120 mm 1); Light source: PinPoint LED 2); Type of light: Visible red light. The linked SICK data sheet is specific to WTB4S-3P5232H.