My travel size contact lense solution doesn't have a screw-off top. In order to refill it you have to meticulously pry it off with a flat-head screwdriver. Otherwise, you would just have
ASDA All in One Contact Lens Solution Travel Pack - ASDA Groceries
Renu Multi-Purpose Contact Lens Solution, Advanced Formula, 16 Fl Oz Pack of 2 + 2 Fl Oz Travel Size
Biotrue Multi-Purpose Travel Contact Lens Solution, 100 ml Flight Pack, Cushions and Rehydrates Soft Contact Lenses Comfortable Wear-Condition, Clean, Remove Protein, Disinfect and Rinse : Amazon.co.uk: Health & Personal Care