The Tow bar on my RV is the type that slides in a square pipe (Not sure what it is called) and has a metal pin that goes right through with a security devise that locks it in position,, Although it all works and I have a 50mm ball on the end it seems loose, will this stiffen up when a trailer is put on the ball ? I can foresee that it will rattle and clunk around,, or is this not the case, or is it something I will have to live with ? Also I have a large trailer that I use for tip runs,, hooked up to a Kia Sedona, it sits nice and square and straight, but when I hook it up to the RV it is far to high at the ball end and looks as if I could do with a 3-4 inch drop plate. Thing is the ball on the RV is fixed/welded to a very heavy metal plate which is welded to the square pipe that goes up the tube. Will I have to get another plate welded on but a bit bigger and lower to square me up ? Or is the centre of the hitch lower on a car trailer ? I thought they were all about 18"-19" from the ground to the top of the ball!! Hope you can understand my twittering`s not easy to explain. Thanking you in anticipation.