New aluminum cylinder with steel sleeve and light weight high compression piston, piston pin, clips and all gaskets are included-Aluminum cylinder with reboreable sleeve-55mm light weight high compression kit with the 10.25:1 compression ratio-Gasket including cylinder head and cylinder base gaskets. ENGINE CASES MUST BE BORED OUT TO FIT THIS CYLINDER!!!!! Any claims for damage or defects to products must be reported prior to installation.