Experienced my first sink/washing machine/dishwasher (all interconnected in the plumbing system) blockage in 30+ years yesterday.
Didn't have a plunger because I've never needed one so purchased this little beauty for the princely sum of £2.99 and job was sorted in a couple of minutes.
https://www.screwfix.com/p/sink-bath...cker/13894#_=p