Leviton 660W Medium Base Snap-In Porcelain Incandescent Lampholder, White 8885 - The Home Depot
DiCUNO E26 Ceramic Light Socket, Standard Medium Base Screw-in Lamp Holder, UL Listed Porcelain Pre-Wired Lead 12 Inches 18 AWG Connector for Halogen CFL Incandescent LED Bulb, 4 Packs - - Amazon.com
Eaton Wiring 660W Porcelain Lampholder, Keyless, Medium Base, #14-10 AWG, 250V, White (Eaton Wiring 604-SP) | HomElectrical.com
Leviton LAMP SOCKETS 660W 250V MED BASE OUTLET BOX LMPHLDR 49875 | Zoro
E26 Medium Porcelain Lamp Socket with 1/8F, 1/2" tall metal hickey and – Antique Lamp Supply