This is a very well designed kit containing all the special tools and steel inserts to repair up to 5 stripped oil drain plugs with the same thread pitch. Luckily (unfortunately?) I only had two broken plugs in my Bobcat tractor's oil pan. The instructions were very clear and the sharp drill, reamer and tap got the job done quickly. I ended up using sealed steel threaded inserts in the tractor's aluminum oil pan. It took about an hour to install both inserts and the tractor is back in action! Highly recommended.