We only use genuine K9 crystal

Small: 1.9" x 1.9" x 3.1" (5cm x 5cm x 8cm)
Medium: 3.94" x 2.76" x 2.36" (10cm x 7cm x 6cm)
Large: 3.15" x 2.36" x 4.72" (8cm x 6cm x 12cm)