Possibly one of the most-frustrating experiences in any AR-15 lower-receiver build is the installation process involved in getting a pivot-pin detent into place. More often than not, trying to do this without a specialized tool leads to detents shooting across your workspace, never to be seen again. Obsidian Arms has its Armorer's Pivot Pin Detent Tool to avoid this frustrating occurrence. The Obsidian Arms Pivot Pin Detent Tool is made from 4140 alloy steel and has been heat-treated and QPQ-finished for enhanced durability. The tool is covered by Obsidian Arms' lifetime warranty, so if you ever break any of their tools, the company will replace the tool at no charge.