Не спрашивал. Лень. Мелкая самая - пофигу какая, а вот со средней хз.

Нашел:

http://www.middleburn.co.uk/chainrings_mtb.php

<div class='quotetop'>Цитата</div>
We offer two types of machining on our chainrings: Slickshift Chainrings which means they have ramps and pins to aid the change from one ring to another, and the Standard Chainrings which don&#39;t have ramps or pins.[/b]