Cut Stringer Stairs 
https://elitestaircases.co.uk/cut-stringer-stairs/
Cut stringer stairs, also known as open stringer stairs, are a type of staircase where the treads and risers are fixed to a cut-out notch in a solid stringer, leaving the profile of the stringer visible on the side of the stairs. Cut stringer stairs are a popular choice for those seeking a contemporary and modern look, and they can be made from a variety of materials such as wood, metal, or glass. The visible profile of the stringer in cut stringer stairs creates a visually striking design feature, making it a popular choice for many architects and designers. Cut stringer stairs are not only visually appealing, but they also offer excellent structural integrity, making them a safe and durable option for any home or building.
