This STIHL chain is a great addition to your outdoor power equipment. It is compatible with STIHL chainsaws and features a 2-stroke engine type. The guide bar size is 18" and the model number is MS271, MS261, MS261 C-M, and MS261 C-MQ. The pitch measures .325" and the use .063". This chain is made in Germany and requires assembly.  and is perfect for your yard, garden, and outdoor living needs.