carbide internal & external threading insert SIZE :11ER/16ER/22ER 11IR/16IR/22IR ... ISO,A,AG,G,W,UN,NPT,ACME,API carbide internal & external threading insert SIZE RANGES ARE 11ER/16ER/22ER11IR/16IR ... in our products.WENLING LIFENG PRECISION TOOL CO.,LTD!!! carbide internal & external threading insert