Brownells A3 Elevation Index Spring Features The Brownells AR-15 A3 Elevation Index Spring is manufactured to precise tolerances that match or exceed original equipment specifications ensuring the elevation index on an A3 flat-top rear sight moves and detents correctly through its adjustment range. A worn or broken index spring can cause the elevation drum to feel loose or fail to hold a set zero undermining confidence in the sight s repeatability. Replacing it with this correctly sized spring restores crisp positive detents at each elevation setting. Reliable elevation adjustment matters most when a rifle is being zeroed or dialed for a specific distance so a properly functioning spring is not a detail to overlook. Sold in a 3-pack this spring gives owners and armorers enough spares to service multiple rifles or keep extras on hand for future repairs. It installs during routine rear sight maintenance without requiring any specialized tools beyond what is already used for standard AR-15 service. Builders assembling a parts rifle from individual components will also find this a useful easy-to-source small part. This spring is a practical low-cost way to keep your A3 rear sight functioning as designed. Brownells A3 Elevation Index Spring Specifications Brand: Brownells Compatible Hosts: AR-15 Color: Silver Quantity: 3 Available At: GrabAGun