This is a brand new long rear fender manufactured in Japan.
It fits Honda Monkey Z50J and Gorilla
It is recommended to use this part when you install a long swingarm on your vehicle.
Easy to install on genuine frame fittings.
Here are several technical informations from manufacturer:

Monkey Aluminum Long Fender Plate Blue

<Features>
It is a custom standard product around the rear, a long fender plate made of aluminum.
It is a high quality fender made in Japan.

<Specifications>
Size 355 x 110 (mm)
Material made of aluminum
Surface treatment Hard alumite finish

<Accessories>
Flange cap bolt M6 x 12mm ・ ・ ・ 4 pcs

<Compatible model>
Monkey / Gorilla (12V) Z50J-2000001 ~ / AB27-1000001 ~
Monkey / Gorilla 3.1PS (6V) Z50J-1600008 ~ 1805927
Monkey / Gorilla 2.6PS (6V) Z50J-1300017 ~ 1510400