4145H Quenched & Tempered Steel
Slick
Spiral
NC23-31 NC26-35(2 3/8 IF) NC31-41(2 7/8 IF)
NC35-47 NC38-50(31/2IF) NC44-60
NC44-60 NC44-62 NC44-62(4IF)
NC44-65(4IF) NC44-65(4IF) NC44-67(4IF)
NC50-67(41/2IF) NC50-70(41/2IF) NC50-70(41/2IF)
NC50-72(41/2IF) NC56-80 NC61-90
NC70-97 NC70-100
Spiral Drill Collar with elevator groove & slip
Non Magnetic Drill Collar