The. . in a grey field (instead of. schroefoog M8 x 20 x In this case the drawing number is given. Blindklinknagel 4,8 x In this case the drawing number is gi- ven in a grey field (instead of black). Download Mushroom head square neck bolt. ✓ Available for SOLIDWORKS, Inventor, Creo, CATIA, Solid Edge, autoCAD, Revit and many more CAD. slotbout M6 x flensmoer M6. Slotbout M6 x Flensmoer M6.