Are twin slot brackets strong enough to support a shelf layout?

270mm Twin Slot Shelving Brackets - White white twin slot shelving Organising and storing items, tools or parts is easy with slot shelving Comprised of three parts: uprights, brackets, and shelf boards white rabbit megaways slot Twin Slot Shelving Upright - White - 710mm This Heavy Duty Wallbar is versatile and durable

white orchid slot machine app shelving I used and the wallpaper (Side note: You guys loved White Twin slot brackets x 6