Air Filter / Kubota K3181-82240Pack Size:1Kubota K3181-82240Baldwin RS3990, Donaldson P778979, J. Thomas 102388, Napa 9978, Rotary 13383, Wix 49978Kubota ZD323, ZD326 and ZD331ID: 2 1/2 ", OD: 4 1/2 ", Height: 9 3/4 "