Hey, With the 'Sellotape' hats you have to be really careful, as there are many sold on the market which arent up to the safety standard!
Just a thought
Hey, i find that the best thing to do is to but citronella from your chemist and mix it with water yourself. You can make alarge amount and this way you know there are no added chemicals etc! Best thing about it is that its REALLY cheap and WORKS!!