The Edison Screw fitting was developed by Thomas Edison in 1909, and is now available in a variety of sizes. The more common are the medium-sized E27 and the smaller E14. The generic term ‘screw fit’ usually refers to E27. Bulbs are simply threaded into the lamp holder in clockwise rotation for installation.
E27 (Edison, 27mm diameter), ES (Edison Screw), MES (Medium Edison Screw).
Candle, CFL Cluster, CFL Spiral, CFL Stick, Golf Ball, Globe, GLS, PAR, Mercury MBF-U, Mini CFL, Plumen Designer Bulb, R63 Reflector, R80 Reflector, R125 Reflector, SON-E, SON-T, Squirrel Cage (decorative), Tubular Bulb.