Ceramic lamp holder : GU10,G5.3,G4.0,MR16,MR11,G12,R7S,etcPlastic lamp holder: E14,E27Cetificate: VDE,CE,ROHS,REACH,Contact information:Jolly Industrial (HK) CO.,LtdEileen / Chen XulingTel: +86-757-80346373Mob:+86-13560039146SKYPE: eileen.chen.2008QQ: 1158034875