The Human Hair Curl Pattern Chart is great for wigmakers to have on hand for client consultations.  Discuss the various curl patterns available and allow the client to decide which style is best.
 
The curl pattern sample ring is made with human hair and includes the following 12 patterns:
 
0.4
0.8
1.0
1.2
1.5
1.8
2.0
2.2
2.5
2.8
3.0
3.2