51-50, I'm off the Heezy,
5150 is a California Welfare and Institutions code which allows police, doctors, etc. to confine a person deemed with a mental disorder.
In other words, Tyler the Creator is a crazy person on the loose, and is deemed extremely dangerous.
51/50 is a watch made by Nixon, the skateboarding brand, and notice he points to his watch in the video.
New Era, a baseball cap company, makes hats called 59Fifty and 39Fifty, thus he’s also referring to the hats, being off the “heezy” (head.)
Lasty, this could be a reference to Hurricane Chris' debut album 51/50 Ratchet, as Odd Future has a habit of using the word ratchet lately
5150 is also the type of Guitar amp head that the Trash Talk members of the TrashWang collective use to play music. ‘Off the heezy’ — heezy = head. 5150 = head.
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