Ushio 1001628 - EKE/HO JCR21V-150W Projector Light Bulb

150 Watt 21 Volt EKE/HO MR16 Shape GX 5.3 Base Halogen Bulb The history on EKE/HO (item 1001628) goes back 10 years or so. Same life as standard EKE (1000306) at 200 h, but EKE/HO has slightly shorter working distance (WD) at 43mm versus standard EKE WD of 44.5 mm. So optically there are some slight alignment differences. The "HO" lamps, have a slightly modified reflector coating that tailors the transmissivity/reflectivity characteristics in the 330nm-490 nm (nanometer) spectral region which was required for the specific photo therapy application. The “ HO” lamp was not designed for general visible light applications like the EKE standard lamp.

(UAI item 1000306). The two are not interchangeable especially if they are looking to replace an EKE/HO with an EKE in a system that is currently employing the EKE/HO type.