There is no distinction made between chariot and chariot, nor any mention made of the drivers of these chariots, though these are included in the chariots. Now by the different colours of the horses doth the prophet distinguish the chariots, and possibly that is all intended by the various colours, though generally interpreters do guess by the colour of the horses what should be the quality and temper of the times pointed at; of which a little: red horses may signify bloody times, a fiery execution of wrath, Revelation 6:4; black, a time of mortality, and wasting diseases, Revelation 6:5.
Related Commentaries of Zechariah 6:2
Zechariah 6:2
2 In the first chariot were red horses; and in the second chariot black horses;