Hi! Today I've received my 350 Jumpsport rebounder as Lauren suggested and I'm so excited! I was wondering if it is normal that it has just three knots for each connector (and not four), is that ok? I think that with three knots I can just have the medium setting (all the three knots are above the connectors). I'm sorry, It's complicated to explain, but I hope you can understand my question :) thank you so much!!