At some point in the next twenty-four hours I’ll get round to using this (I’ve just had a late breakfast and then lunch including a bar of chocolate and small packet of crisps). There are three tubes are of varying strengths and when I tried pulling each one with my hands as you would pull a Christmas cracker the easiest one (yellow) seemed a bit too easy. But then I haven’t done any reps and I wasn’t using it properly. Will post my findings. Cost £10.