Review title is Amazing find but has problems. [SEP] Best thing since bread! Incredibly natural look and movement. Fooled everyone who thought it was my natural hair.  Cap is tight, possibly 21-21.5" diameter. Not big head friendly. Sadly, the hair quality is not as good as I first thought. After 3 wears, tangled and frizzed badly. I washed and conditioned the synthetic hair with little help. Used heat, blow dry and flat iron, with some benefit. I do not want to straighten the hair as it is thin and sparsely sewn. Sadly, I am running out of ideas to keep it looking good. Will eventually copy the sewing pattern and replace the hair with better quality fiber. Really is a fantastic find. Cannot wear without the pony tail as it us sewn in using a minimum of weft.