General Electric

Two GE M1000s.  The finned one on the left is probably a mid-1960s model, while the nonfinned version on the right uses the 1973 design.  Both are 700-watt mercury vapor.

Two original 1959 GE M250s, both 175-watt mercury vapor.

M250R (circa 1974), 250-watt mercury vapor.

Newer-style M250, 175-watt mercury vapor.

M250 PowrDoor (1980s-present), 70-watt HPS.

M250 with square refractor, 150-watt HPS.

More of the current M250s, 250-watt HPS (left) and 175-watt mercury vapor (right).

Two original 1959 GE M400s, both 400-watt mercury vapor.  The one on the left has a silver finish, while the one on the right is painted grey (a standard for subsequent GE fixtures).

M400A2 (1987-1996), 400-watt mercury vapor.

M400A (1967-1986), 400-watt mercury vapor.

M400 (1997-present), both 250-watt HPS.  The semicutoff version is on the left, the cutoff on the right.

M400As, both 400-watt units (mercury vapor on the left, HPS on the right).

The original M400A full-cutoffs, both HPS (250 watts on the left, 400 watts on the right).

M400A2 full cutoff, 1987-1996 (above left) and M400 full cutoff, 1997-present (above right).  Both are 400-watt HPS.

M400A2, 250-watt HPS.

M400, 400-watt mercury vapor.

M400, 250-watt metal halide (left) and M400 PowrDoor, 400-watt HPS (right).

Two GE M400s, both 250-watt HPS.  The 1997 model is in the foreground, the mid-1980s version in the background.