517Medium Formation TCI Tricone Bits 
The 517 features aggressive chisel tungsten carbide inserts on the heel rows and inner rows.This design provides a fast drilling rate and added cutting structure durability in medium-to-medium hard for-mations.The HSN rubber O-ring provides adequate sealing for bearing durability. 

637Hard Formation TCI Tricone Bits 
The 637 bits can be used to drill hard and abrasive forma-tions.Wear-resistant tungsten carbide inserts are used in outer rows to prevent loss of bit gauge.Maximum numbers of hemisphereical-shaped inserts are used in all rows to provide cutter durability and long life. 

617Medium-Hard Formation TCI Tricone Bits 
The 617 features robust chisel tungsten carbide inserts on the heel row and conical on the inner his design provides a fast drilling rate and added cutting structure durability in medium to medium hard formations.The HSN robber O-rin provides adequate sealing for bearing durability. 

437Soft Formation TCI Tricone Bits 
The 437 tcli bits are used to drill low compressive strength,very soft formations.TCI bits maximize the use of bothconical and chisel tungsten carbide inserts of large diameters and high projection.This cutting structure design,combined with maximum cone offset,results in high bit penetration rates.The deep intermesh of cutter rows prevents bit bailing in sticky formations.