The Equalizer Express Blades were developed from daily use on hundreds of different vehicles. The BFE1400 is the most used size and is perfect for slicing through wide bands of urethane. It works well in all places where you plunge cut or angle cut. The BFE1401 and LBE1403 blades are perfect for removing glass that is not broken. Their narrow (1-1/2" wide) blade is more flexible, which puts less stress on the glass. On some vehicles, the urethane is far below the glass, but there is a limited amount of vertical space inside the vehicle. In situations like this, you will need one of the 12" blades (LBE1402 or LBE1403). They perform the same function as the BFE1400 and BFE1401, but are 2" longer. On other vehicles, specifically the Windstar, Transport, Camaro, and Caravan, the urethane is very deep below the dash. This is also true on the Century Class Freightliners and some motor homes. For those vehicles you should keep one of the 14" blades (RLE1404) in your tool box. Some areas require side-to-side cutting. This is more common around very radical curves in the glass, and in vehicles that have corners with a sharper-than-90 angle. It can be difficult to get all the way up into these corners with a square-end blade, but the round tip of the BFE1420 will reach up into the corner and cut the urethane. Some vehicles such as Ford Windstar, Econoline, Explorer, Ranger, newer Chevy/GMC and Mazda pickups have a moulding with a piece of metal inside. If you cut into the moulding the metal insert makes it difficult to cut. Also, many encapsulated glasses have a very dense encapsulation material that is difficult to cut. The BFS1421 and BFS1422 are designed to hold the blade below the moulding and prevent the blade from cutting into the encapsulation. A permanently-attached, self-lubricating nylon spacer lets the blade move easily back and forth while holding the blade under the lower lip of the moulding or encapsulation.All blades are made of a specially-formulated steel that is hardened and then tempered using a cold molecular-aligning process. This makes the blades very flexible. Each blade will easily remove over 50 windshields when used according to directions. Made in the USA.