Sir 1000 R16 Internal Threading Holder 1" Round Rh Boring Bar Internal Lay Down Threading Holder For Size 16 Inserts Sir 1000 R16 Internal Threading Holder 1 Inch Round Right Hand Boring Bar Internal Lay Down Threading Holder For Size 16 Inserts Threading Holder For Size 16 Inserts Tmx Toolmex Part #6-Sir-1000-R16