I exercise using the EA Sports Active programme for the Wii, and I've been hunting for ages for resistance bands long enough to replace the very weak one provided with the software. The industry standard for bands and tubes seems to be 120cm, which just isn't long enough (even though I'm not especially tall). The bands in this pack, used with the handles supplied by EA Sports, are just right. It would have been nice to be able to buy the things singly - I'll never need the weakest one as it's similar to the EA-provided one - but the others are stronger and will keep me happy for a couple of months.
It seems a bit daft to me that virtually all such products only come in 1 length.... Herd instinct?