The Octagonal Shaped Furibo 2.5kg is extremely heavy and should be used with great care.
Suburi with a heavy Furibo is a excellent full body strengthening exercise. It improves one's sense of balance and stabilizes the center of gravity, which is a vital aspect when training Japanese martial arts. It also develops stable lower body and proper "tenouchi" or a grip required for every martial art style.
This is a even heavier version of the 1.5kg version. It's quite a challenge and needs to be handle with care to avoid back injuries. Made with Japanese Red Oak.
What is Japanese Red Oak?
The Red Oak Wood used for Japanese Bokken, also called 'Akagashi', greatly differs from the Red Oak Wood referred to when speaking about North American Bokken.
While the North American Oak and Japanese Oak are related, the Japanese Oak tree is evergreen, due to this it does not have a conspicuous open grain like the American White and Red Oak.
The open grain structure, of the American Oak wood produces soft areas which are more prone to impact damage.
Akagashi on the other hand has a structure that is uniformly hard, has excellent dent resistance and has better impact strength than American Oaks.
Nowadays Akagashi is a quite rare and expensive even in Japan, and is mostly used for making high quality Bokken.