Muzerdo 110PCS Standard Sae and Metric Bearing Steel Tap and Die Rethreading Kit. You really should look to get as much diversity in the sizes of the taps and dies as you can. That way you will be able to pull the right size out of the box when you need it. Wrenches – All tap and die bits need to be mounted in a wrench. Broadly speaking, they are all roughly the same, with a few notable exceptions. The tap wrench from Muzerdo, is the best on the market. Construction Material – Steel is the base metal used in the construction of these sets – but not all steel is created equally! Look for steel alloy or, even better, Titanium tipped cutting surfaces. The better the metal the tougher the tap and die so they so they can cut into more materials and they will stay sharper for longer. Metric/SAE – The size of the tap and die is also important. Metric is of course the European measurement system, SAE are based on US sizes (so use inches instead of millimeters). This is important as you may struggle to use a SAE tap and die set on a vehicle with metric measurements. If the car is made in the US, it probably uses SAE measurements. If it is a European carmaker, it’s probably the opposite. If can look for a set with dual Metric and SAE compatibility of course then you don’t have t. Metal Storage Case – More than with many other types of tools, the storage case is an important part of the tap and die set. Frankly, because these sets can come with multiple parts, you do want a case that is well designed to keep all the little pieces well organized and safely stored. This tap and die set is designed to thread cutting: tap is used to process internal thread, while the die is for external thread. They are perfect for most hand threading applications Specifications: Number of Pieces: 110pc Material: Tungsten steel. 17.68 x 12.99 x 2.17 inches. We reserve the right to cancel any order for any reason at any time. We are not responsible for undeliverable addresses. Your feedback very important to us, after you get your package and you are. Satisfied with our service. If you have any problem with your order / any questions please before leave any type of feedback. Thank you for shopping at our store.