Here is the lock (anti-shake) washer that goes between the nut and the brake pipe/tube and the high pressure flexible hose. We have found both internal toothed and external toothed washers in this spot so type is not critical. You'll need one nut and one lock washer for each end of the hose. So screw nut onto hose then washer then pipe. This item is for ONE washer. Oh that was easy!  See item G5/68 for the nut. Yes Grade 8.