Steel toothed (ST) bits available in the following types (series):

• N – the standard bit with open journals for various types of drilling;
• NE – the improved bit with open journals, tungsten carbide inserts on the gauge for various types of drilling;
• NRS – the standard bit with sealed roller bearings characterized by reliable lubrication of the bearing support for the responsible types of drilling;
• NFS – the standard bit with sealed friction bearings characterized by reliable lubrication of the bearing support for the responsible types of drilling;
• NRSE – the improved standard bit with sealed roller bearings characterized by increased rotation resource and improved wear resistance and improved cutting structure and bit stabilization for extremely difficult types of drilling;
• NFSE – the improved standard bit with sealed friction bearings characterized by increased rotation resource and improved wear resistance and improved cutting structure and bit stabilization for extremely difficult types of drilling;
• NA – the standard bit with air cleaning for different types of drilling operations in the direct air circulation;
• NAR – the standard bit with air cleaning for different types of drilling operations in the reverse air circulation;
• NAS – the standard bit with air cleaning characterized reliable lubrication of the sealed journals and increased rotation resource for various types of drilling operations in the direct air circulation.

The cutting structure of cones corresponds to the IADC (International Association of Drilling Contractors) classification of roller rock bits by the first two digits of the IADC code in the bit designation.

Design feature of bits:

• T — additional tungsten carbide insert on heel rows;
• W — a tungsten carbide coating on cone bodies;
• D – diamond coated tungsten carbide inserts on the gauge of the cones;
• P — a leg pad;
• G — tungsten carbide inserts on the shirttail of the legs;
• C — additional central nozzle for cleaning cones.

Examples of designation to bits:

165,1 NA21 — standard ST bit with air circulation and IADC 212;

215,9 NRS13GC — standard ST bits with sealed roller bearings and IADC 137 having carbide inserts on the shirttail of the legs and an additional central nozzle;

215,9 NFSE13DGPC — improved ST bits with sealed friction bearings and IADC 137 having diamond coated tungsten carbide inserts on the gauge of cones, tungsten carbide inserts on the shirttail of the legs, leg pads and additional central nozzle.