Catering staff had been whinging about a sideways spurt of water from her J. Lewis fitted kitchen mixer tap.
Hard water here so I assumed limescale blockage at the outlet nozzle. Beyond finger tight so I applied modest force with some grips.
Turns out that the hot supply is fed up the Swan neck in a plastic tube and the plastic nozzle (now in two pieces) simply plugs in. Perhaps threaded or glued to the outer.
Installed 6 years back but not currently apparent on the JL spares list.