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.