These stretchy clear silicone wig caps give an ideal non-slip surface. They also help with fit if a wig is not quite the right shape or tightness. They are sized to sit on the pate of the head, but can be trimmed if needed.
Silicone wig caps are available in sizes based on the head circumference:
3 - for Amelia Thimble and tiny BJDs
4 - for Barbie, Fashion Royalty, Puki Puki and 23cm BJDs
4/5 - for Sybarite, Kingdom Doll, ModsDoll, Ficon
5/6 - for Gene, Tyler, YoSD, Ruby Red In Motion
6/7 - for Ellowyne, Evangelines, CEDs, smaller head MSD (like Narae)
7/8 - for most MSD and 22" Tonner American Models
8/10 - for 60cm BJDs, Ruby Red Fashion Friends