That's the weight for two tubes.
Have you weighed any 32c butyl tubes lately? Conti Supersonic 18/20c are 50g each, so 70g 32c would needs be condom-thin.
@gbj_tester started
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Have you weighed any 32c butyl tubes lately? Conti Supersonic 18/20c are 50g each, so 70g 32c would needs be condom-thin.