Pure suet with no other ingredients mixed in.  We only recommend this suet if you are having trouble with Starlings and Grackles.  They tend not to like it but woodpeckers and chickadees still do.  However, the woodpeckers and chickadees don't like it as much as the suet with nuts or insects mixed in (like the Smorgasbug Suet).  So we recommend using that suet with the Recycled Upside-Down Suet Feeder in order to be Starling and Grackle proof while still offering the chickadees, nuthatches, and woodpeckers their favorite type of suet.