I always keep spare nozzles on hand. Nothing worse then when i've been particularly messy, and not had a spare one of these in my kit. So lesson learnt. When I mess up, I change up.
3 per pack
Note: to remove old nozzle, carefully place knife tip between bottle neck and nozzle and gently ease up in several places. Once loosened, you can use a pair of pliers padded with kitchen towel to grip nozzle neck and gently pull up.