ergonomics

An ergonomically adjusted bicycle handlebar with the right stem, grips and optimally placed spacers ensures a healthy sitting position and reduces pressure points and tension. By individually adjusting these components, riding comfort can be significantly improved and the risk of long-term damage reduced.

handlebar clamp

For mountain bikes, a distinction is made between 3 diameters: 35 mm, 31.8 mm and 25.4 mm.
On aero racing bikes like the Aerium, the handlebars and stem are one - this saves weight and has a positive effect on aerodynamics.
City bikes usually have a diameter of 25.4 mm. It's best to just look at the product description of your bike to be completely sure.

material

Carbon handlebars are lighter and offer better vibration dampening, resulting in a more comfortable ride, while aluminum handlebars are more robust and usually less expensive. However, carbon is more prone to cracking if handled improperly, while aluminum is more durable and resistant to impacts due to its higher strength.