Dormer DORA100364 A100 HSS Jobber Drill Bit 3/64in OL:38mm WL:16mm Dormer A100 series general purpose HSS jobber drills are suitable for use in the majority of general purpose engineering applications. They have good self-centring capability on a wide range of materials and are suitable for both hand and machine use. DIN338RN BS328 ISO235 Tip diameter: 3/64in. Working length: 16mm. Overall length: 38mm.