The Alpinestars MTB Bionic Jacket protects your spine, forearms, elbows, shoulders, and chest, so you can hurl yourself into the stratosphere without a worry in the world. Tough polyurethane and impact foam protects your vitals while all-over stretch mesh construction keeps you from overheating. The Bionic is also compatible with neck protectors, so you can do battle with hairy singletrack in full armor.