the brush is soft and can prevent scoring the surfaces
the inner diameter is a standard 32mm/1.25inch size,allowing the attachment to be used with household vacuum of 1.25 inch,the hair length is about 0.98inch
It's a must have for anything with your vacuum hose--blinds, baseboards, pattern dieing, ceiling fan , return air vents, any kind of furniture or doors with decorative grooves, regular wood furniture, ANYTHING! The hairs are stiff enough to loosen up most things and soft enough not to scratch sensitive surfaces.
The inner diameter is 1-1/4inch(32mm),so outside diameter of the vacuum wand or hose connect to it should be smaller than 1-1/4inch(32mm) which is 31mm or 30.5mm.
