Bucklos (WHO?) is almost the only company offering a 25.4 mm diameter bar. 25.4 used to be the industry standard until manufactures needed you to buy new bicycles and changed everything and tried to make you feel stupid for riding an older bike. (See 26” tires)
So Bucklos (WHO??) offers two shapes in a number of lengths in aluminum and carbon so you don’t have to feel like an idiot for wanting to ride your favorite bike.