Boring Head Dia: 3. Boring Head Height: 3-5/32 Max. Offset: 1. Boring Capacity: 12~225mm. Boring Bar Dia: 3/4. Cross Hole Dia: 3/4. Min. Graduation: 0.0005. Bar Thread :1-1/2-18 Shank: R8. Quantity of Boring Cutters: 12 PCs.