These are wigs modeled by Amerian Girl dolls, with suggested sizes for these 18" dolls.  The full line of Monique wigs is available in sizes for American Girl and other dolls.  If you don't see a wig or style you would like, please ask and I'll see what I can do to help. 

Majesty Wig for American Girl dolls $23.95

Kathy Wig From $15.90

Marie Wig From $17.64

Brittany Wig From $17.58