We study three-atom inelastic scattering in ultracold ${}^{39}\mathrm{K}$ near a Feshbach resonance of intermediate coupling strength. The nonuniversal character of such resonance leads to an abnormally large Efimov absolute length scale and a relatively small effective range $r_e$, allowing the features of the ${}^{39}\mathrm{K}$ Efimov spectrum to be better isolated from the short-range physics. Meticulous characterization of and correction for finite-temperature effects ensure high accuracy on the measurements of these features at large-magnitude scattering lengths. For a single Feshbach resonance, we unambiguously locate four distinct features in the Efimov structure. Three of these features form ratios that obey the Efimov universal scaling to within 10%, while the fourth feature, occurring at a value of scattering length closest to $r_e$, instead deviates from the universal value.

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• Ultracold collisions
• Atoms
• Molecules
• Ultracold gases
• Magnetic moment
• Polarizability
• Feshbach resonance
• Optical lattices & traps