ES (E27) Edison Screw Cap, 27mm Diameter
BC (B22d) Bayonet Cap, 22mm Diameter
SES (E14) Small Edison Screw Cap, 14mm Diameter
SBC (B15d) Small Bayonet Cap, 14mm Diameter
GX5.3 Pins 5.3mm Apart.
GU10 Twist and Lock Cap Pins 10mm Apart.