Proton boots

Proton boots are footwear from the Generation 1 continuity family.

Proton boots are an article of Transformer clothing. Their purpose is obscure.

Fiction

Cartoon continuity

Brawn sarcastically announced that the prospect of fighting Bumblebee caused him to quake in his proton boots. Microbots

Since Brawn was not wearing boots at the time, this statement was probably metaphorical.