JBJ 12 Gallon Nano Cube Deluxe Replacement Splash Guard (MT-402-SG) Replacement JBJ 12 Gallon Nano Cube Deluxe Splash Guard (MT-402-SG). Replacement JBJ 12 Gallon Nano Cube Deluxe Splash Guard (MT-402-SG). For the old style compact fluorescent version only. Will NOT work with the new style all-LED version.