This is a standard AR-15 cut bolt.
Yes. The Phase 5 Tactical AR-15 Black Complete Bolt Carrier Group will work with multiple calibers such as .223, 5.56, and 300 Blackout and will work in an AR15 with a 223 Wylde barrel.
Yes, that is correct.
This is a complete bolt carrier group, no additional parts needed.
Yes, this bcg would be compatible with .300 BLK.
Yes, this BCG will be compatible with .350 Legend.
This is the AR-15 cut.
This is compatible with: Caliber: 5.56 NATO / .223 Rem / 300 BLK
All Phase 5 WSI assemblies and components have a lifetime warranty against any manufacturing defects. The manufacturer also recommends to have the products installed by a licensed gunsmith. The manufacturer will not warranty products damaged by customers during installation.
Unfortunately Phase 5 has not provided that information, even on their own site. We recommend contacting them directly, they should be able to provide you with that information. You can reach them here: https://phase5wsi.com/support-contacts/