and the side effects can involve serious health issues. our effort is to create something simply from various selections and from rearranging these selections. the weight of the keys are on the heavy side. when i was there, they could have done anything they wanted, i was just the mother, watching; really the nurses were taking care of my daughter. we are interested in trying some cross country skiing to get a feel for whether it is something we would like before buying our own equipment. there is a small filter screen in the water inlet valve. 