Ushio MR16 GU5.3 & GX5.3 Base Rim Mount Lamp Holder – BulbAmerica
MR16 Halogen Lamp Socket
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MR16 Sockets and Lamp Holders - Lighting Accessories – BulbAmerica
Socket Base Plug 5-50pcs Mr16 Mr11 Gu5.3 G4 LED Lamp Holder Bulb Base with Wire | eBay
MR16 MR11 G4 GU5.3 MR11 Ceramic Base Socket Lamp Holder