Like the pop top on a soft-drink can, he thought.

Thinner cans and smaller pop tops arrived in the late 1980's in an effort to save aluminum.

At the industry's annual Interbev conventions in the early 1990's, engineers debated the next step for pop tops.

There remained, however, a fundamental problem with the pop top: both beverage and air had to share a single opening.

He glanced down at the pop top.

The drink was previously sold in standard aluminum cans with pop tops.

Mr. Schmidt said vacuum-sealed jars with pop tops were the "industry standard" for baby foods.

Lavern Morsch collected the pop tops from soda cans to use as her medium.

The pop top from his first illegal beer.

It was the only Rawls' record to reach Billboard's pop top ten.