It's a rubber cup that you insert, then remove and empty every few hours. I think for a while there was a disposable cup product (called "instead") but the keeper is supposed to last 10 years. Costs about $30, so I figured it would pay for itself in less than a year. I've had it for a couple of months. Still getting used to it, but it's especially easier when travelling than cloth options, and you don't have to empty it very often. It's getting more comfortable as I get used to it. More comfy than tampons, for example, because it doesn't need to go as far up as a tampon does.
If you decide to buy one, I'll tell you my "friend code" so when you order one I get a $5 kickback.
I've never succeeded in getting the Ingdirect referral kickback. Maybe I'll have more luck with the Keeper.
Hope this thread is not too graphic for the squeamish! Altho I guess it started out as a diaper discussion so we've just moved on to different bodily functions.