Emtek Solid Brass Mercury Lever With Square Rosette (Brushed Nickel Finish) - The Mercury lever door knob shown here measures 5 inches in length with a 2 7/8 inch projection. The square rosette measures 2 1/2 inches overall. Includes the two levers and door rosettes. Functional sets also include the lever latch, face plate and strike plate. This set is made for modern doors and it fits any door thickness between 1 3/8 inch to 2 1/4 inches thick. Functional sets come with a 2 3/8 inch back set latch - and a 2 3/4 inch back set may be requested at no additional charge. This door lever set comes complete with mounting hardware. Handing is required for leversets. A customer service agent will contact you when the order is placed to discuss handing options.