@Liu2016 and @Faherty2016 classify as a young field object. The L4 object is a member of the $110-150~$Myr old AB Doradus moving group [@Faherty2016; @Liu2016] and has been classified as an intermediate-gravity object based on its IR spectrum [@Gagne2015c]. All three targets have estimated evolutionary model masses of $20-25~M_{\mathrm{Jup}}$ based on their bolometric luminosities [@Faherty2016].

In addition, we obtained Gemini/GNIRS high-resolution spectra of and re-reduced Keck/NIRSPEC spectra for and . In Section \[sec:rotvel\] we describe the analysis of our high-resolution spectra, in Section \[sec:obs\_datareduc\] we describe the *Spitzer* observations and data reduction, in Section \[sec:var\_id\] we describe how we identified variables and in Sections \[sec:amplitudes\], \[sec:inclination\] and \[sec:periods\] we describe our results in the context of brown dwarf variability amplitudes, inclination angles and rotation periods.

Target Rotational Velocities and Maximum Periods {#sec:rotvel}
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and have high-resolution NIRSPEC-7 data from Keck/NIRSPEC in the Keck Observatory Archive (Program IDs C34NS, N58NS; PI: Charbonneau). We additionally obtained a high-dispersion spectrum of using Gemini/GNIRS (PID: GN-2017B-Q-58). We used the 111 l/mm grating and the long camera ($0.05''$ per pixel) with a $0.10''$ slit, centered at $2.3~\mu$m. We obtained four 600 s exposures taken in an ABBA nod pattern. The data were reduced using a 