Review on 🔩 E-Z LOK 319-5 External Threaded Insert, C12L14 Carbon Steel, Meets AISI 12L14, 5/16"-18 Internal Threads, 7/16"-14 External Threads, Length 0.437", Made in USA (Pack of 10) by Maurice Arnold

Unlike other more expensive inserts like Time-sert, they do not require special tools, greatly increasing the price of repair inserts. I've been using them for many years. I don't trust the red locking compound on the threads. I take it off and use my own red LocTite. You can get them with thin walls or regular ones.