It has a small gear on the back that moves, resulting in sometimes adding 6 kilograms, sometimes subtracting 5-6 kilograms. I fixed it so it doesn't move with a little silicone, and now it permanently adds 6 kilograms, which is why I give it 2 stars. If it subtracted 6 kilograms, it would receive 5 stars and 1 Michelin.