Other than T05H weighing in at 50g, the other Butterfly rubbers weigh at or below 48g. G1 at 47g is the lightest ESN rubber, which used to be among the heaviest back in late 2000s to early 2010s. Karahashi Takkyu's rubbers in tokuatsu/extra thick/>=2.1 and TB ALC head size. Not explicitly...