Let’s start with what to avoid. Many mass-produced men’s underwear relies on synthetic fabrics such as polyester, nylon, or low-quality spandex blends. These materials are cheap and stretchy, but they lack breathability—a fatal flaw for reproductive health. They trap heat and moisture against the skin, creating a warm, damp environment that’s a double threat: it raises scrotal temperature (undermining sperm health) and fosters the growth of bacteria and fungi, leading to irritations like jock itch or more severe infections over time. For Amamble, these fabrics never make the cut—we refuse to compromise your health for cost or convenience.