SICK ZTB18-4PR4A1D06 Photoelectric sensors. SICK ZTB18-4PR4A1D06 is a photoelectric sensors in the Z18 Simple Sense family. SICK identifies this exact configuration as manufacturer article 1110981. The official technical record specifies Functional principle: Photoelectric proximity sensor; Functional principle detail: Background suppression; Dimensions (W x H x D): 13.6 mm x 44.2 mm x 33.3 mm; Housing design (light emission): Hybrid; Thread diameter (housing): M18; Mounting system type: M18, head/M18, base. The linked SICK data sheet is specific to ZTB18-4PR4A1D06.