Bionic - the ball is really designed for horses so I got one from my local saddlery store - yes it was a bit pricey... I think it was £24 but my sheep love it so I'm glad I got it!! ! Bruckley - I put some small sheep nuts in it. The only thing I would advise if anyone gets one, is to put the snacks in the hole, but then put some tape across the lid because even though it seems to lock, I found that it sometimes came off and all the nuts would fall out in one place, which the sheep loved but that's not the idea!! I'm not able to use it at the minute because with all the rain we've had the grass is so long.. unlike when I took the video!