Lamp Caps and Holders Together with Gauges for the Control of Interchangeability and Safety Part 2: Lampholders (Edition 3.0; Amended in Accordance with Supplements: A-1970@ B-1971@ C-1972@ D-1975@ E-1975@ F-1980@ G-1980@ H-1987@ J-1989@ K-1992@ L-1994@ M