| Series | 556 | 
                                        
                                            | Certifications | RoHS w/ 6C exemption, IK07, IP66, NEMA 4X | 
                                        
                                            | Status | Active | 
                                        
                                            | Features | Constant Intensity | 
                                        
                                            | Mounting Hole Size | 1.00" (25.4mm) | 
                                        
                                            | Output | Single Color | 
                                        
                                            | Emitted Color | Red | 
                                        
                                            | LED Position | Internal | 
                                        
                                            | Lens Style | Domed | 
                                        
                                            | Lens Color | Tinted, Diffused | 
                                        
                                            | Voltage | 18-48 VDC | 
                                        
                                            | Resistor | Internal Resistor Included | 
                                        
                                            | Mounting Method | Nut/Washer | 
                                        
                                            | Max Panel Thickness | .187" (4.27mm) | 
                                        
                                            | Mounting Torque | 40 | 
                                        
                                            | Mounting Torque Unit of Measure | lb-in | 
                                        
                                            | Polarity Sensitive | Yes | 
                                        
                                            | Typical Current (mA) | 7.3–8.2 | 
                                        
                                            | Typical Intensity (mcd) | 400 | 
                                        
                                            | Termination | Screw Terminals | 
                                        
                                            | Termination Finish | Hot Solder Dip | 
                                        
                                            | Housing Material | Brass | 
                                        
                                            | Lock Washer | Zinc w/ Yellow Chromate | 
                                        
                                            | Nut | White Nickel | 
                                        
                                            | Operating Temperature | -30°C to +85°C (-22°F to +185°F) | 
                                        
                                            | Storage Temperature | -40°C to +100°C (-40F to +212°F) | 
                                        
                                            | Housing Finish___housing_finish | White Nickel |