M-Wave QRIR Top Ahead Cap

My son has a frog 58 road bike and wants a handlebar extension for mounting his phone, computer and lights, There is not enough space on the bars for a regular extension as it snags the interruptor brake levers so I am looking to mount an extension bar on the top tube. I think you sell just what I need: The M-Wave QRIR Top Ahead Cap combined with the M-Wave QRIR Cockpit Universal Bracket. Am i correct? If i order those two parts will I get a 20cm bar attached to the top tube? Thanks, William