Hi, I have the larger of the 2 Yamaha top boxes available in the uk, it takes2 full face lids on their sides. It fits directly onto the top rack mounting which moves the pillion handles outwards. Takes seconds to remove with ignition key , It is waterproof and well made. Yamaha recommendation is not used in conjunction with side cases but I ignore that and just keep speed down when fully loaded, other half loves the back rest pad !