575W Halogen Bulb Replacement for ETC Source Four Jr Light Bulb by Technical Precision - 120V Track Light Bulb with G9.5 Medium Bi-Pin Base - 3250K Tungsten Halogen Lamp Bulb - 1
EiKO HPL Source Four Lamp (575W, 115V) HPL575/115V B&H Photo
ETC Source Four Leko 5 degree in San Francisco- San Francisco
New and Used Source Four Ellipsoidal Lighting Fixture for sale
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ETC Source Four Jr Knob, X-Y, lamp set - Part #7060A4007 - Pack of 5
How To: Change a Source Four Lamp - YouTube
Source Four turns 25 read as we take a look back to 1992