it has a big tooth quaife gear kit fitted,the teeth are huge compared to a standard box to give more strength and shot peined makes them stronger on top of that
helical appose to straight cut so its not as noisy (but also not as strong as straight cut)
there is no recipt for the build and it has been sitting a while,altho i do think this price is very cheap considering the gear kit alone is £2800 plus vat