What is the Mc David Groin Strap? Fully adjustable neoprene wrap with Velcro fastener. Relieves symptoms related to groin pain & sports hernia. When can I use it? For the relief of symptoms related to groin problems such as Adductor Tendinopathy, sports hernia & Gilmores Groin. Which size do I need? One size fits most. How does it work? The Mc David Groin Strap is a fully adjustable neoprene wrap that goes around the thigh & fastens with Velcro. It can be positioned & adjusted to apply pressure to the groin region. This pressure reduces the amount of muscle force that can be generated from the groin muscles, which relieves the groin pain & groin stiffness symptoms of groin muscle & tendon problems (Adductor Tendinopathy), sports hernia & Gilmores Groin.