uxcell 2 Piece Plastic Encased Aquarium Bubble Air Stone, 12", White/Green Product Name : Aquarium Air Stone; Material : Mineral, PVC Plastic Color : Green, White; Stone Length : 30cm/12" Overall Size : 31.5x 2x 1.3cm/12" x 0.8" x 0.5"(L*W*H); Hole Diameter : 3mm/0.12" (Inside), 4.5mm/0.2"(Maximum Outside) Net Weight : 156g Package Content : 1 x Aquarium Bubble Air Stone