NCT Chaser are inter-changeable.If one Peace Of a chaser set is damaged is beyond use. Then same No. peace Of the other chaser set lying in stock may be used and there will not be any difference in threading performance and the damaged set can be replaced without the necessity of replacing entire set. NCT Tangential Chasers are manufactured from imported High Speed Steel which must pass exacting metallurgical standard.Experienced heat treatment with the automatic imported heat treatment plant and imported Testing equipments,assures that they will perform satisfactorily in service and produce quality threads within the tolerance for which they are intended. FOR MORE INFORMATION SEE OUR WEB http://nationalcuttingtools.page.tl