An ox goad has an exterior and an interior, from seven [handbreadths] for the blade, [and] from four [handbreadths] for the prod; [these are] the words of R’ Yehudah. R’ Meir says: They do not have [an exterior and an interior]; [the measures of] four [handbreadths] and seven [handbreadths] were mentioned only with regard to remnants [of ox goads].