| Series | 21M |
| Dimension | 12 x 50 x 42.5 mm |
| Interface | PNP NO/NC |
| Input function | Key disable on/offTeach Contrast (switching point) |
| Principle of operation | Contrast sensor |
| Principle of optical operation | Diffuse sensor, Focused |
| Special optical feature | Coaxial Optics |
| Beam characteristic | Focused |
| Light type | White light |
| Light spot size | Ø 3.5 mm at 19 mm |
| Range | 17…21 mm |
| Connection | Connector, M12x1-Male, 4-pin |
| Housing material | Zinc, Die casting, Powder coatedAluminum |
| Material sensing surface | Glass |
| Operating voltage Ub | 10…30 VDC |
| Approval/Conformity | cULusCEUKCAWEEE |