So long as the balls are not weather damaged, or are very discoloured, or have damaged / frayed nap, or have been worn down to practically threadbare, then we can take them. 

i.e. Balls have been knocked over the fence, into the bushes, onto a roof etc. then left out in all weathers, will be weather damaged / will have become discoloured. 

i.e. If the balls have been used to death, then the nap will be have become practically threadbare or will have become frayed. 

We can not take any balls that have been used on clay courts, as they will have become very discoloured red / brown. (Ball used on artificial clay surfaces should be fine, provided they have not become too discoloured) 

If any of the balls are in any of the above conditions, please don’t put them into the bin. 

Also, we can not take the standard yellow coloured low pressure / mini balls. ( i.e. green dot / red dot / stage 1 / stage 2 Etc. ) The dual coloured low pressure / mini balls are fine, provided they are in good condition ).