ER, TG, SYOZ, and DA collets all have unique measurements. Even if the markings have been worn off, by noting the shape and carefully measuring your collets you can determine what types and sizes of collets you have. Measure the length (L) and depth (D) of the collet. Then use the guide below for selecting replacement collets.

ER Collet L D
ER 8 13mm (.51”) 8.5mm (.33″)
ER 11 18mm (.708″) 11.5mm (.45″)
ER 16 27.5mm (1.08″) 17mm (.67″)
ER 20 31.5mm (1.24″) 21mm (.83″)
ER 25 34mm (1.34″) 26mm (1.02″)
ER 32 40mm (1.57″) 33mm (1.3″)
ER 40 46mm (1.81″) 41mm (1.61″)
ER 50 60mm (2.36″) 52mm (2.05″)

For best results always use a Power Coat nut with your collets, tightened to proper specification using an accurate torque wrench.

techniks_ER_collet_measurement

ER Collets

TG Collet L A
TG 75 47mm (1.85″) 27mm (1.06″)
TG 100 60mm (2.36″) 35mm (1.38″)
TG 150 76mm (3″) 51mm (2″)

techniks_TG_collet_measurementsTG Collets

SYOZ / EOCĀ  Collet L D
EOC 8 26mm (1.026”) 14.4mm (.567″)
SYOZ 20 34mm (1.34″) 20mm (.78″)
RDO 20 34mm (1.34″) 20mm (.78″)
407E 34mm (1.34″) 20mm (.78″)
EOC 12 34mm (1.34″) 20mm (.78″)
SYOZ 25 52mm (2.06″) 35mm (1.38″)
RDO 35 52mm (2.06″) 35mm (1.38″)
462E / SYOZ 25 52mm (2.06″) 35mm (1.38″)
EOC 32 60mm (2.36″) 43.7mm (1.72″)

SYOZ Collets

DA Collet L A
DA 180 1.625″ 1.035″
DA 100 1.438″ .769″
DA 200 1.188″ .531″
DA 300 1.000″ .375″

DA (Double Angle)