Towards the end of recording of Radiosurgery, New Found Glory invited Bethany Cosentino of the Indie Rock band Best Coast to provide backing vocals on this track. Cosentino is a fan of the band, and they became friends through Twitter. Guitarist Chad Gilbert explained on the band's website: "The story goes, I wanted to get in to see their sold out show at the Troubadour and didn't have a ticket. I tweeted them half kidding about putting me on the guest list! Come to find out they were NFG fans and totally hooked me up. Since then we've been buds!"
"Sloop John B" is a traditional West Indian folk song, and it was a huge hit for The Beach Boys in 1966. They tweaked the lyric, "This is the worst trip since I've been born" to "...I've ever been on" as a wink to acid culture.