Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: Would these fit a Blackberry headphone?
Document: The day that I got these foam covers, I put them on those ear buds and my cat decided that night to get through the cord. I read a review of someone recommending to put some dish soap along the length of your headphone cord to discourage them from doing so and thought I would pass along that little tidbit of information as well.
Gave my old in ear earphones new life. Great replacement part. Tight fit, tore first one putting it on, got hang of it and then they went on great. Was going to throw out the old earphones as they had no pads and would not stay in my ear. Now they stay in. Wonderful.
I purchased these because of the great reviews and very few people complaining that they ripped or were overly difficult to put on. They did not disappoint. They do take a little patience to get on, but I've put them on 3 different sets of ear buds and no rips or issues. Surprisingly, they even fit on my iPhone 5 headphones. The iPhone 5 standard headphones are good quality, but they would always fall out of my ears.
These are more sturdy and go on easier than other brands I've purchased. I'm using these on my blackberry headphones and my original iphone headphones. I will definitely order these again.
I am very pleased with my purchase. Great product for a very reasonable price. I would purchase from this seller again.
I brought them for my friend and she love them.I would recommend  and purchase them for myself. I also received them quick.
Shipped super fast, work great! More than I would ever need, but at least this purchase will last me a lifetime! :)
Good elasticity, specially for apple headphones. I would recommend it for everybody. Liked the price that I got them for.
I have been using this for couple of months and so far good! I approve the quality and I would buy it again if I need more.
8 pairs for that price is great as these things last a while unless you lose em. Shipping was quick also. I would recommend it
Answer: I used them on another brand, but all these earphones look about the same size - mine were just over 1/2 inch across (diameter) before foam bud added - easy, turn them inside out and roll it back over the bud.