BTC options expiring 13SEP26, 1 days out, with the forward at $77,224. Open interest is $106M in calls and $108M in puts, put/call 1.02, and max pain is $77,500. At-the-money implied volatility is 13.5%. Where a strike is listed on both venues the cheaper ask and richer bid are visible side by side; the arb scanner flags any gap that exceeds fees. Strikes shown are within 60% of the forward. All BTC expiries.