Under Armour UA Mens Micro G Limitless Running Trainers Synthetic-and-mesh Rubber sole Form-Fitted Compression Half-Sleeve - Wraps the foot in a tight later to provide support. Synthetic Overlay On The Lateral Side - Lightweight protection. Leather On The Medial Side - For added durability. Leather Toe Cap - Adds extra durability to the front of the shoe. Micro G - Gives the shoes a responsive, bouncy feel.