It's a light saber
belt BUCKLE.
The Big Bang Theory Season 12, Episode 24
Ooh, look, a new Batman belt BUCKLE.
The Big Bang Theory Season 2, Episode 20
It said right there on the invitation,
"Buckle up for fun!"
The Big Bang Theory Season 10, Episode 19
All right. Let's BUCKLE down and work.
The Big Bang Theory Season 3, Episode 4
Well, then, BUCKLE up.
The Big Bang Theory Season 1, Episode 4