The Mechanix, by Metallica band members, Dave Mustaine on Lead guitar, and James Hetfield on vocals. (1982)
The four horsemen by Metallica, without Dave Mustaine on vocals nor guitar. (1983)
(Edit: Should also probably mention that the lyrics completely changed here compared to the other 2)
Mechanix by Megadeth band members, vocals and lead guitar from Dave Mustaine. (1985)