Well, this one isn’t for the weight weenies, but other than that, its the perfect solution for your rear derailleur. Our super strong magnetic connection has more than 10 kg of holding force, probably more than enough to lift your bike. But it will break loose before you damage the Quantum shifter or your derailleur in case of accidental impact. Should it get bumped, it will just immediately snap back into place. CNC machined from non-leaded steel, with a beautiful black oxide finish. Choose the adapter size that fits your derailleur. Approximate weight: 18g.