Magnets seem to be creeping into mountain biking at the moment. There are two pedal brands (that we know of) using them for a halfway house between clips and flats
; bottle holders
that use magnets for a quicker release and even a Canyon concept bike
making use of magnets for suspension.
The latest to throw their hat into this ring is the brand MagSuck. Since the advent of narrow wide chainrings, dropping chains are certainly less common these days however, for those that are still having issues or still begrudgingly use a chainguide, this could be an attractive solution.
Based out of China, MagSuck produce a chainring that uses small magnets between each tooth to keep the chain firmly in place. MagSuck goes so far as to make the claim it will fully eliminate chain drops. The brand also claims that there is reduced chain noise when using the ring as the chain shakes around less and finally that there shouldn't be any loss of power as you crank the pedals.
Material 7075 T6 aluminum
Options RaceFace Cinch, SRAM GXP, M8000, 104BCD
Weight 67-70 grams
Price USD $69.50-$89.50
The MagSuck ring has a claimed weight of 67 grams for a 32 tooth ring, which is about on par with a more conventional chainring thanks to the holes drilled into the ring to insert the magnets. Plus if it means you can ditch a chain guide, then you're cutting that weight as well.
MagSuck sell the chainring worldwide for USD $69.50-$89.50 depending on what model. They also sell a full crankset if someone wants to do more of an overhaul on their drivetrain.More info here