Artist: B-Real of Cypress Hill
Claim: "Inhale, exhale, just got an ounce in the mail" from Black Sunday's "Hits From The Bong" (1993)
Breakdown: Everyone inhales and then exhales, that's basic human physiology. As far as the ounce in the mail, the United States Postal Service can ship packages as light as a letter and as heavy as 100+ pounds. They will deliver it to any approved address, including B-Real's location.
Given B-Real and Cypress Hill's penchant for marijuana, we are assuming this ounce is the green stuff. And as the late comedian Mitch Hedberg once said, "my mailman is my drug dealer, he just doesn't know it."
Conclusion: B-Real did get an ounce in the mail.