The Lovibond 138180 is a 5V replacement lamp used for several series of Lovibond spectrophotometric colorimeters. Product Specifications Voltage: 5 V Compatible Instruments: PFXi Series: PFXi-195, PFXi-880, PFXi-950, and PFXi-995 PFX Series: PFX-195, PFX-880, PFX-950, and PFX-995 Purpose: This bulb is a critical spare part used to provide the light source for automatic transmission measurement and color grading of liquids.