knob

knob /ˈnɑːb/ noun
plural knobs
knob
/ˈnɑːb/
noun
plural knobs
Britannica Dictionary definition of KNOB
[count]
1 
: a round switch on a television, radio, etc.
2 
: a round handle on a door, drawer, etc.
3 
chiefly British : a small lump or piece of something
4 
British, informal + impolite : penis

with knobs on

British, informal
: with extra things added