Saru Saru no Mi, Model: King Kong

The Saru Saru no Mi, Model: King Kong is a Mythical Zoan-type Devil Fruit that allows its user to transform into a King Kong at will. It was eaten by Roshi, the former vice admiral of the Marines.

Etymology

 * Saru (猿) means "ape" in Japanese

Strengths and Weaknesses
The main strength of this fruit is that it allows the user to transform into a giant, red monkey, gaining an extreme boost in strength to match his size. In this form, Roshi's limbs grow, giving him abnormally large arms and legs. In addition to a full and hybrid transformation that are available to all Zoan Devil Fruit users, this fruit grants Roshi an ability to grow even larger, based on his anger. This fruit has no apparent weaknesses, aside from the standard Devil Fruit weaknesses.

Usage
Roshi uses this frut's power to launch powerful punches at his oponents.