Down and Dirty Initiation Kit: suction base provide secure grip on smooth, flat surfaces. Harness compatible strap on o-ring style. Made of durable phthalate free Sensafirm PVC material. Small dong insertable 4.25 inches by 1.5 inches diameter. Medium dong insertable 6 inches by 1.75 inches diameter. Large dong insertable 7.25 inches by 2 inches diameter.