A preferred gingival finish line in a veriety of cases. A chamfer finish line can be the finish line of choice in a variety of cases. Preferred by many dentists, easy to achieve, created by most burs used with rounded edges. The chamfer can accept different crown materials and designs. This finish line can be used for metal margins, as well as porcelain margins, as long as space permits.
Recommended - metal finish line.   

The shoulder bevel finish line is a finish line design for tooth preparation in which the gingival floor meets the external axial surfaces at approximately a right angle with a slanted edge. This finish line is usually preferred when a metal collar is planned, to lower stress concentrations on the porcelain at the margins. 
Recommended – Metal collar.

The chamfer finish line has a curved angle between the gingival floor and the axial surfaces. The deep chamfer allows more space for porcelain, giving the technician more freedom to create an esthetic restoration.
Recommended – Porcelain margin or metal margin.

The shoulder finish line is a design for tooth preparation in which the gingival floor meets the external axial surfaces at approximately a right angle. This is recommended when porcelain is at the margins, usually allowing more space as well. The finish line of choice when a porcelain butt margin is required.
Recommended – Porcelain margins.

The Knife edge finish line design is a long slanted edge, typically used in a periodontally involved tooth or where tooth wall reduction is limited. This preparation while conservative on tooth structure is more limiting with the crown design.
Recommended – metal finish line or metal collar.