Lister TR1 air cooled Diesel, 1 cylinder, 775cc Valve stem seals included. Equates to 657-33301 Weight of set and packing approximately 270g Pack size 245 x 353 x 25 The manufacturer recommends that the TR1 is decarbonised after 1000 hours, an exercise that will require many of the gaskets and joints contained in a top set.