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Low-mass (< 1.2 Solar mass) main-sequence stars lose angular momentum overtime, leading to a decrease in their magnetic activity. The details of thisrotation-activity relation remain poorly understood. Using observations ofmembers of the $\approx$700 Myr-old Praesepe and Hyades open clusters, we aimto characterize the rotation-activity relation for different tracers ofactivity at this age. To complement published data, we obtained new opticalspectra for 250 Praesepe stars, new X-ray detections for ten, and new rotationperiods for 28. These numbers for Hyads are 131, 22, and 137, respectively. Thelatter increases the number of Hyads with periods by 50%. We used these data tomeasure the fractional H$\alpha$ and X-ray luminosities,$\mathit{L}_{H\alpha}/\mathit{L}_{bol}$ and $\mathit{L}_X/\mathit{L}_{bol}$,and to calculate Rossby numbers $\mathit{R}_o$. We found that at $\approx$700Myr almost all M dwarfs exhibit H$\alpha$ emission, with binaries having thesame overall color-H$\alpha$ equivalent width distribution as single stars. Inthe $\mathit{R}_o-\mathit{L}_{H\alpha}/\mathit{L}_{bol}$ plane, unsaturatedsingle stars follow a power-law with index $\beta = -5.9 \pm 0.8$ for$\mathit{R}_o > 0.3$. In the $\mathit{R}_o-\mathit{L}_X/\mathit{L}_{bol}$plane, we see evidence for supersaturation for single stars with $\mathit{R}_o\lesssim 0.01$, following a power-law with index $\beta_{sup} =0.5^{+0.2}_{-0.1}$, supporting the hypothesis that stellar coronae are beingcentrifugally stripped. We found that the critical $\mathit{R}_o$ value atwhich activity saturates is smaller for $\mathit{L}_X/\mathit{L}_{bol}$ thanfor $\mathit{L}_{H\alpha}/\mathit{L}_{bol}$. Finally, we observed an almost 1:1relation between $\mathit{L}_{H\alpha}/\mathit{L}_{bol}$ and$\mathit{L}_X/\mathit{L}_{bol}$, suggesting that both the corona and thechromosphere experience similar magnetic heating.

The Factory and the Beehive. V. Chromospheric and Coronal Activity and Its Dependence on Rotation in Praesepe and the Hyades