The Klein Recycler features a "klein weld". They are like a hybrid of an external and internal recycler. They are designed like internal recyclers, but the drain doesn't just go straight down to the bottom of the can. It first exits the can and then loops back inside. The reason this is done is so the drain does not get in the way of the percolator. You don't want them to interfere with each other and a "klein weld" is the best way to make sure the doesn't happen.