Mixer taps working loose

[Anticrossmodulation]

Our mixer taps (bathroom sink) keeps working loose, I'm able to slightly tighten the nut (see image) however not tight enough, basically using pilers. Is there a correct tool or method, like a box screw etc ?

 

[moonlight]

You could buy a set of tap back nut box spanners and tighten the nut. £8.19 Unfortunately as your tap has flexible connections the tap may again come loose. Be ready with the spanners.

Mono Tap Back Nut Box Spanner

4 piece set includes 3 double ended box spanners and a tommy bar. Sizes: 8, 9, 10, 11,12,13mm

www.toolstation.com