The sidecut of your board is measured as a radius in centimeters. It is an important part of your board's geometry that affects how your board turns. The larger the radius—or number—the more shallow of a sidecut your board has. Conversely, the smaller the radius of your board, the deeper the sidecut is and, therefore the more aggresive it will initiate a turn.

DUAL INDEPENDENT SIDECUT
Essentially, the sidecut is divided into two radii that are centered on the inserts and meet at the waist. The deeper sidecut sits towards the tail and automatically follows through once the larger sidecut is engaged.

RADIAL SIDECUT
A radial sidecut is a single single sidecut on the board. It is centered to the inserts and the waist and, therefore rides backwards the same way that it rides forwards.

TWIN
A true twin board has symmetrical and centered geometry: the sidecut, inserts and tip and tails. It rides the exact same way both frontwards and backwards.

DIRECTIONAL
A board can be directional based on a few things in its geometry. It can be directional if it has an off-centered sidecut or a Dual Independent Sidecut. It can also be directional if its inserts are back of center. As well, a board can also be directional if it has a different sized nose and tail length or width. Essentially, a directional board is designed—although not limited to—go in one direction.