This International Standard specifies the dimensions of reduction sleeves with external 7/24 taper (Nos. 30, 40, 45, 50 and 60) for tools with Morse taper shanks (Nos. 1 to 6). All these sleeves allow driving of tools having Morse taper shanks which have a tenon at the small end of the shank; some sleeves allow driving of tools having Morse taper shanks which have an axially tapped hole in the shank : — with the use of an incorporated screw for sleeves 30 x 1 — 40 x1 — 40 x2 — 45 x1 — 45x2 — 45 x3 — 50 x 2 — 50 x 3 — 50 x 4 — 60 x 3 — 60 x 4 — 60 x 5; — with the use of a draw bar for sleeves 30 x 1 — 30x2 — 40x1 — 40x2 — 40x3 — 45x1 — 45x2 — 45x3 — 45 x4 — 50x2 — 50x3 — 50 x4 — 50x5 — 60 x 3 — 60 x 4 — 60 x 5 — 60 x 6. Morse tapers conform to ISO 296 and 7/24 tapers are in accordance with ISO 297 and ISO 2583.