Did you ever catch the meat of your finger in one of the large MagFloat scrubbers!? I was doing Tango's 50% and I wasn't paying attention. I got a pinch of my thumb meat caught between the two magnets. They slammed down onto my poor thumb! OWWWWWWWWWWW!!!!! I think I'm dyin'!!!!! I even pulled some skin off. OWWWWWW!
It's two magnets with velcro scrubbers on one side and felt on the other. You put one on the inside, one on the outside and use it to scrub the stuff off tank walls (diatoms in my case). His magnets are big and very strong. The freakin thing snapped together on my thumb like a trap. :(