Reddit reviews Draper 6 Piece Metric Tubular Box Spanner Set - 28967
We found 1 Reddit comments about Draper 6 Piece Metric Tubular Box Spanner Set - 28967. Here are the top ones, ranked by their Reddit score.
Double endedtwo tommy bars 100 mm and 150 mm longZinc plated for corrosion protection
So im pretty sure that it is an 11mm nut.
The safest option is to buy this
http://www.amazon.co.uk/Draper-28967-6-Piece-Box-Wrench/dp/B0001K9RVW/ref=dp_cp_ob_diy_title_1
It covers all mixer tap nuts and costs less than £5 delivered.
Then climb under the sink and tighten the nut. Im trying to add a picture at this point but i have no idea how.