Songfacts®:

• "Rain" is the first collaboration between Aitch and AJ Tracey. It is a high-energy banger during which each rapper slings out sixteens about money and their bedroom prowess.
• The pair come together on the hook during which they boast about making it rain with their stacks of cash and iced-out jewelry.
  
  Big fat stack in my bag, when I un-zip that, finna' make it rain
  Cuh, when we run down, it's rain
  Right wrist and left wrist, that's rain
  
  Fat Joe and Lil Wayne first popularized the use of the phrase "make it rain," meaning throwing money at women in a club. On their 2006 track "Make It Rain" Wayne rapped about tossing stacks of cash at the strippers, so that it appeared to be raining money.
• Tay Keith came up with the piano-heavy beat. The Memphis producer is also responsible for hits by Drake ("Nonstop"), Blocboy JB featuring Drake ("Look Alive"), Travis Scott ("Sicko Mode") and Eminem ("Not Alike").
• The song's Arrad-directed visual is set in Los Angeles. Both rappers make it rain with stacks of dollar bills and various pieces of jewelry.
• Aitch has huge admiration for Tracey's contribution to this song. "We were writing our verses together for this and I think AJ wrote his faster," he told Apple Music. "I would say me personally, as a listener, I think AJ goes in harder. It's like a Michael Jordan/Scottie Pippen situation. AJ wouldn't have got the dunk if I hadn't thrown it up to him like that. So I'll happily take the assist on 'Rain.' My man went hard. That's all I can say about this one - it's crazy."