Lays down the dimensions of these reduction sleeves. Applies to 7/24 taper Nos. 30 - 40 - 45 - 50 and 60 and Morse taper Nos. 1 to 6. Morse tapers Nos. 4 - and 6 being either with positive drive (sleeves of type B) or without positive drive (sleeves of type A). These sleeves permit driving of tools with Morse taper shanks with tapped holes with the aid of an internal screw. The form of this screw and its fixation in the sleeve are left to the manufacturer' s discretion.