1. Description: E27 vintage, antique and industrial lamp holder, compatible with E27 medium base bulbs, especially vintage Edison bulbs, suitable for decorative pendant lighting projects. (Package: 4 colors mixed) 2. Features: [High Quality]: UL listed, CE and RoHS certified; [Sturdy]: Bulbs could be held firmly; [Heat resistant]: High up to 600C; Maximum power is 600W; [Material]: Aluminum cover and ceramic lamp holder. 3. Application: 1) Used most often with e27 vintage Edison bulbs and for retro lighting. Create an antique and classic atmosphere to modern life. 2) Addable lampshade. Different added shades and adjusted wire length could bring various decorative effects. 4. Installation: Easy to install. Connect the wires correctly to the positive/negative pole, then assemble all the parts. An installation instruction is attached for your reference.