SICK WTT12L-B1561 Laser distance sensors. SICK WTT12L-B1561 is a laser distance sensors in the WTT12 PowerProx family. SICK identifies this exact configuration as manufacturer article 1072608. The official technical record specifies Functional principle: Photoelectric proximity sensor; Functional principle detail: Background suppression, Optical time-of-flight; Housing design (light emission): Rectangular; Sensing range max.: 50 mm ... 3,800 mm 1); Sensing range: 100 mm ... 3,800 mm 2) 1); Accuracy: 3) 4). The linked SICK data sheet is specific to WTT12L-B1561.