Review on 🔩 Vittoria Presta Valve Cores (10-Pack), Silver - High-quality Replacement Accessories for Optimal Tire Maintenance by Matt Simpsons

These are definitely higher quality valve cores than inner tubes, which are relatively cheap anyway. The outer body is zinc plated or steel plated and the inner shaft is brass. The plastic cover is thick. If you have an expensive bike, replace the valve cores with these to keep the issue going. I don't know how many times I've had problems with cheap valve cores getting stuck, not letting air through, or stripped threads, so that's the ticket. Made in China of course, but the quality is excellent.