RDO/OZ COLLETS RDO Collets are designed for high gripping strength collet system and are sometimes known as OZ collets. Lexis RDO Collets / OZ collets system is recommended for milling, drilling and boring applications. Lexis RDO Collet / OZ Collets metric sizes range starting from 2mm Dia to 32mm with 0.5mm incremental and Inches sizes starting from 1/8” to 1” Inch. RDO 16 Collet (Form A Style) RDO 20 Collet RDO 25 Collet RDO 35 Collet RDO 44 Collet OZ 16 Collet OZ 20 Collet OZ 25 Collet OZ 35 Collet OZ 44 Collet