Inte r nal Toolholde r - Q uick Guide Positive type ISO Insert Min. bore diameter DMIN (mm) Style Designation & Application Material Page 0 10 20 30 SVJCR/L Internal sphere cutting Steel ø16 ø20 4-27 Insert : VC** SVUCR/L 50˚ Boring & internal profiling Steel ø16 4-27 Insert : VC** SVQCR/L ø13.5 ø21.5 Steel 25.5˚ Boring & internal profiling 4-28 Insert : VC** Carbide ø13.5 SYUBR/L Steel ø20 60˚ Boring & internal profiling 4-29 Carbide ø20 Insert : YW** SYQBR/L Steel ø17 ø21.5 30˚ Boring, undercutting & profiling 4-29 Insert : YW** Carbide ø17 SEZPR/L Steel ø5.5 ø6.5 Back boring 4-14 Insert : EP** Carbide ø5.5 ø6.5 SDZXR/L Steel ø14 ø16 26˚ Back boring 4-25 Insert : DXGU Carbide ø18 SDZCR/L Steel ø14 ø16 30˚ Back boring 4-23 Insert : DC** Carbide ø18 SVZBR/L 50˚ Back boring Steel ø20 4-26 Insert : VB** SVZCR/L 50˚ Back boring Steel ø16 4-28 Insert : VC** 4-4