Top quality from MBD, Lambretta head nut kit consisting of 4 thick cylinder head washers, three special cylinder head nuts and one extended cylinder head nut for the cowling.
 
There is nothing better on the market, Mark Broadhurst has designed and tested them over many years.
 
Torque the nuts down to 18 - 20lbs ft
 
Retighten the nuts at 500 - 1000 miles from a new rebuild.