In order to ensure the best result after using an erectile dysfunction pump, tension rings (or penis bands) must be put in place to guarantee that the erection stays in place throughout sexual intercourse. Erection tension bands can be left on safely for up to 30 minutes to allow for successful intercourse, non-toxic so the partner is safe too. To accompany to all the demands of our customers, we offer a wide variety of sizes so everyone can find their fit. Diabetes may create blood flow complications but with the help of tension rings, diabetics can go along living their activities. All orders over $99 receive FREE shipping. If you have any questions please feel free to contact us toll free at 877-977-7709, we are open Mon-Fri 9-5 EST.