We are offering 3.9mm bone locking bolt. Specifications cat no. : s.s.: 259.240 to 259.960ti : 404.324 to 404.360thread dia : 4.9mmcore dia : 4.0mmhex. Socket : 3.5mmhead dia : 8.0mmdrill bit for threaded hole : 4.0mmscrew driver : 4.5mmscrew length : 64mm to 76mm (with 4mm diff.) 80mm to 100mm (with 5mm diff.)indication : with 9mm & above tibia, femur, supra condylar, pfn, recon nails.