The Acquamark cork line is a high quality colmated cork.  These corks have the ageable lifespan of Natural Cork, but are closer to the price of an agglomerated or overrun cork.
Colmated corks are Natural Corks that were not quite flawless enough to make a grade, but are then filled in with agglomerated pieces, resulting in an ageable, but economical cork.
Dimensions: 45mm x 24mm
About Cork Dimensions...
Most bottles tolerate a range of cork dimensions and still produce an acceptable seal. Wider corks create a tighter seal, but may be difficult to insert with small, handheld corkers. Micro-agglomerated corks compress less easily than whole, natural corks, and a smaller diameter agglomerated cork may have the same fit as a wider whole cork. Longer corks reduce the initial headspace in the bottle, and can also affect changes in ullage during long aging.