This is a set of brass parts that replaces the very fine and delicate parts, that could be prone to breaking. Should they break on a full assembled and painted model it is going to be very difficult or impossible to do a repair neatly. These two cast parts replace kit parts G186, 192 and 193. Note you will need to drill a hole through the assembled nose wheel strut kit parts as in stage 94 of the instructions. to accept the brass tube supplied.  Note you will need to clean up some casting sprue gates from the parts and the odd small brass 'inclusions' that may appear through the casting process.