The Form 400 here is still in excellent condition overall, and still has an ancient clear GE Bonusline 400 watt mercury lamp inside! The lamp was made in 1964, but I am not sure when this Form 400 was manfactured, although the Form 400 was made from 1955 to 1960 to my knowledge. Enjoy the photos!
You can see the vintage GE Bonusline BT-37 lamp in the luminaire, also I think the ribs in the reflector are designed for a certain light distribution, likely Type III.
