Polyester Lycra is a popular material for rash guards due to its stretchability, durability, and lightweight properties. The Green Hill IMMAF Approved Rash Guard made with Polyester Lycra is likely to be a high-quality product that has passed specific safety and performance standards required for use in official IMMAF competitions.

The IMMAF approval indicates that the rash guard has undergone testing and meets the required standards for use in competition. However, it is important to note that this approval does not guarantee the quality or safety of the product for other purposes.

When selecting a rash guard made with Polyester Lycra, it is important to ensure that the product is the correct size and fits properly. It is also important to follow the manufacturer's care instructions to maintain the quality and longevity of the product.

Overall, the Green Hill IMMAF Approved Rash Guard made with Polyester Lycra is likely to be a comfortable, durable, and high-quality option for those who engage in martial arts training or competition.