100%  Satin Inside 
 
Our Sizing Chart:
NB: 0-3 Months > 13-16 inches
XS: 3-6 Months >16-18 inches
S: 6-12 Months >18-20 inches
M: 1-4 Years >20-22 inches
L: 5-10 Years >22-24 inches
ADULT: 11+ Years > 24-26 inches