HumanoidDescription for R15

Hello, today I wanted to mess a bit with the characters using the HumanoidDescription system, but I saw that there are properties like LeftArm, but my game is in R15 so is the system avaliable in R15 or do I have to mess with the characters some other way?

HumanoidDescription should automatically apply the appearance to any rig, regardless of the rig type.

Yes, I know, but I want to set the body parts because my game works with the blocky bodyparts and I want to make sure that imported HumanoidDescription has these blocky parts

Nvm. Found out that setting for example LeftArm to 0 sets the whole arm to blocky style.