I have noticed that I have been given 6 brown chain ramps in my rebuild kit but I can see that in Dempseys rebuild book it shows 5 black and 1 brown, the brown being slightly different. Porsche PET shows them all the same with a part no of 911 105 222 05 all 6??? My brown ones have a no 1 928 400 581, again really confusing. Can anyone shed a little light on this ( please ).