You want the colour or the material? It's kinda hard to guess the material just by looking - seems like regular fabric of some sort to me. The colour could be tan, or buckskin, or just orangey-brown or mid-brown. Or do you mean the garment? Maybe a laced jerkin, or a laced vest or a short tunic, or... I'm gonna stop giving suggestions until I'm clearer what you're trying to name.
It looks really light and drape-y for suede, doesn't it? I mean, I agree that it seems like it's trying to give a suede-like impression, but do you think the material in the image is actually suede?
Nah i don't but i guess the OP is really asking what that sort of garment would be made of ... leather would be my first thought, although in the middle ages it wasn't unusual for people to use untreated hides , or for that matter garments woven out of wool or flax
Raw hides are stiff and very light in color. Water can render them soft again, but will also make them putrefy. They need to be tanned before being made into garments. Before the advent of chemical tanning agents, hides could be tanned with brains and wood smoke.
It is either a "chamois fabric" or "fleece" of some sort. It's like a fluffy flannel. I'm betting it's the chamois fabric, however, as that is designed to resemble the leather. The garment itself I couldn't locate an image quite like the one shown. It appears to be a modernized version of a sleeveless jerkin.
I was looking at a fabric glossary, Here. There are so many types of fabric it could be. Perhaps, you could go off of what fit the story/setting. Don't think they had nylon in the late middle ages, or whatever time period that is supposed to be from.
Possibly some hideous vinyl/plastic cosplay outfit made in China, or goatskin. ...the look that is most popular on the fringes of Brighton folk scene, btw, thinking bard.
I'm going to make the opposite assumption and assume you are asking for the name of the garment itself, not the material. I agree with @BayView that it's a jerkin, though of a simplified, rather "modern Halloween costume" take on the idea.
Ooh, a career choice for zombies. Bayview taught us to always use the word zombie when you have a chance so don't blame me.