The world’s most girth-tastic penis implant is available in three sizes: L, XL, and XXL. “Nobody wants a small,” says James Elist, M.D., the Beverly Hills urologist who calls his invention the Penuma. “So we don’t have a small, we don’t have a medium. We start from large.”

Nobody wants a small. If there’s one global, irrefutable truth, it’s that all men dream of being enormous—even the ones who are already big. Among the many patients I interviewed for this story were several well-hung gentlemen who’d nonetheless paid Elist $13,000 to slice them open and enhance their penises with a sheath of silicone. Consider the 39-year-old accountant from outside L.A. who had trouble explaining precisely what led him to get his Penuma in 2014. His wife had no complaints. (“He was very well-off,” she told me; his pre-surgery erections were eight inches long.) When I pushed him, repeatedly, about his motivation, he finally stammered, “I don’t know. I think I just wanted it bigger.”

Another guy, a 43-year-old mechanic from Arizona, told me he got an XL Penuma inserted two years ago because “I realized, well, nothing about me is average or normal, and I didn’t want my sexuality to be average or normal anymore.” After the surgery, he said, his boners increased from six and a half inches to eight and a half inches, and the Penuma “gave me this crazy amount of stamina. Like, I can go for two hours. And I have more control over my orgasms. I mean, I can be going like a Mack truck and still hold back.”

And then there’s the 43-year-old plumber from Northern California whose six-inches-plus, his wife says, “had never been an issue for me.” And yet her husband was convinced that he wasn’t satisfying her: “I didn’t feel like I was doing my job like I was supposed to.” This feeling of inadequacy led to bouts of erectile dysfunction that tormented him until he was fitted last July with an XL Penuma. Now the plumber and his wife get busy four or five times a week.

“He’s been a sexual maniac,” the wife told me. “He has erections all day long every day now. We haven’t had this much sex since when we first got together.” And that was 20 years ago. Getting the Penuma, the plumber said, “basically saved our marriage. I wish I had done it sooner.”

The average erect penis is about five inches long and four and a half inches in circumference, according to a 1996 Journal of Urology study. (Feel better?) Yet by one estimate, nearly half of all men think their packages are smaller than average. Blame porn if you want, or our cultural predisposition to always think bigger is better, or some hardwired Darwinian impulse. Whatever the cause, it’s hardly news that men obsess about the relative size of their members and what that size says about them, physically but also socially. Beyond its sexual function, the penis plays an undeniable, if subtle, role in establishing pecking order, whether at the urinal or in a locker room. Size matters, and not just in bed.

But until Elist—an affable Iranian-born father of three with a mischievous, slightly goofy laugh—got FDA clearance for his implant in 2004, the only procedures available for growing a man’s manhood were temporary, or potentially damaging, or disgusting, or all three. To this day, some surgeons cut the suspensory ligament in the groin so the penis will hang lower, potentially giving the appearance of greater length (but sometimes making stand-at-attention erections tricky). Other doctors inject collagen gel, or your own fat, or insert cadaver cells into the penis, leading to temporary gains (but sometimes to misshapen, lumpy results).

In Tijuana, there’s a doctor who will inject a Brazilian product called Metacrill, which is not approved for use in the U.S. (one doctor I talked to compared it to liquid plexiglass), and there’s a surgeon in Cairo who’s developed a procedure to rotate a flap of groin fat into the penis to make it larger. Still, even as breast implants have become a $300-million-a-year business in the U.S., men have largely been left to make the best of what God gave them. In a world that has always devoted greater resources to diseases affecting more men than women, elective cosmetic surgery has long been an industry focused on females.

That’s begun to change. Especially over the past five years, procedures such as calf and cheekbone implants have increased as men shake off the stigma and embrace the prime drivers of such surgeries in women: vanity and self-affirmation. Without exception, the Penuma patients I interviewed said that their lives had improved since getting the implant. And it wasn’t just about sex. To have continued to settle for the status quo, they said, would have been to deny their potential in every area of life.

By this point you may be wondering: How have I not heard about this? The answer: Elist is currently the only doctor authorized by the FDA to insert the Penuma, and he has all the patients he can handle without doing any marketing other than a basic website. A 66-year-old surgeon with 13 patents to his name, Elist has inserted about 1,300 of his implants in men from all over America and from other countries around the world. The procedure has a 95 percent success rate, according to a five-year clinical study Elist commissioned and presented at an industry conference. That study is part of an ambitious expansion effort spearheaded by his son, a Harvard man who took a leave from his job at a top consulting firm to help his dad make Penuma huge. Elist is petitioning the FDA for clearance that would enable him to begin selling the devices to other doctors and teaching them how to perform the procedure. But until that happens, he’s the only game in town.

Elist’s urological career began in 1976, when he came to the U.S. as a medical resident from Tehran. Back in the ’80s, he was the lead author on the first scientific paper that linked cigarette smoking to impotence. Today, in addition to his Penuma surgeries, he is one of L.A.’s go-to guys for prepping adult ritual circumcisions. (Men who want a bris must be conscious to receive the mohel’s blessings, and Elist has a reputation for his skill at administering local anesthetic.) He is also an infertility expert. In his office on Wilshire Boulevard, he has a bulletin board labeled mission accomplished that is covered with photos of babies born with his help. Still, it was the nagging sense that he’d failed to accomplish another mission that led Elist to invent the Penuma.