I've heard of the alternator that is ~5 lbs. lighter than the average one.
Which brand/type alternator is this?
What years/models came with this alternator?

1969 Dodge Super Bee A12 (440 Six Pack, 4-speed, Dana 60 4.10)

1972 Plymouth Road Runner (400, 4-speed, 8.75" 3.23)

1974 Plymouth Duster 360 (360, 4-speed, 8.75" 3.23)