Extra long studs for use with long stroked cranks and packer plates on small block PX (80, 125 &150cc), and all small block cylinders  - FALC, Malossi, Polini, Quattrini, Parmakit Etc. 
  The length of standard studs are simply too short to fit all the washers and nuts and torque down correctly. Made from hardened and tempered steel, then hand machined.
  These have a 6mm spanner slot top and bottom to help fitting (instead of double nutting!)
 
Size: M7 x 155mm long
 
4 are usually required per engins, price is for 1