difficult to put on keeps collapsing while i am drying my hair [SEP] i have curly hair and thought it was time to buy a diffuser attachment for my hairdryer i measured the mouth portion of my hairdryer before i purchased this it said a opening would be a good fit it was extremely difficult to put on over my hairdryer well after using some creativity lots of finger and hand muscle and a bit of frustration i stretched it over the hairdryer opening then while using it it collapsed several times while i was drying my hair this was even more frustrating than putting it on the hairdryer itself i still may return it i usually air dry my hair i do not recommend unless you need for travel and have no better option