Seiha Seiha no Mi

Appearance
The fruit looks like a grey square fruit with spirals on it.

Powers
Consuming the fruit allows the user to gain the powers and properties of a 4 dimensional shape.

Usage
The fruit operates on the dimensions of space rather than time, meaning it does not allow the user to move into a time free dimension merely allows one to walk among an higher dimensional plane, this affects anything the user directly has on him or the user considers part of him unconsciously.

Because of how dimensions work once triggered the fruit allows the user to see in a truly 3 dimensional way. Seeing all sides of an object simultaneously as well as inside it. This visualization ability allows the user of this fruit to perceive things virtually no other fruit will ever allow. The user is still limited to the visual limitation he had in a 3 dimensional world as they're also translated by the fruit's powers.

An interesting property of moving through 4 dimensional space is that the user can literally disappear and reappear anywhere in the third dimension in a sort of "teleportation". The teleportation isn't instantaneous obviously but it is pretty versatile, and gruesome in some cases.

Trivia

 * Wikipedia's article on 4 dimensional space