My daughter is constantly wearing through the knees of her trousers. I was disappointed that I couldn't find any reinforced knee trousers for her so thought I'd try these as they are "slim" despite them being boys. She's quite short for her age so I sized down. They look ok on her, she doesn't look like she's in boys trousers and she's says they are comfortable. Best bit is they look like they will last, at least longer than some of her others. Please do some styles for girls with the iron knee! Mine can't be the only girl that needs them.