As mentioned, they fit the T4E Smith & Wesson, PPQ and TPM1 in .43 caliber. They hit very hard and have slightly more recoil. In my testing, they weigh 5.422 grams. They clustered fairly well, 2-4 inches, about the same as regular rubber balls. The only thing to expect is that they fall a little more. Shot a little low due to the weight. I don't have a chronograph to check the speed. But I would like to know. I would say 250-280 fps. Packaging wise they came in a resealable plastic bag in the letter box but either on delivery or elsewhere it was open and they were loose in the letter box, be careful when opening. They can fall anywhere. Also, they are coated with oil, you can wash and dry them. I have made. I understand why they are coated, they can be prone to rust. Overall very satisfied with purchase, quantity, price and performance. Don't look at other Riot Balls before you buy these! They are amazing! You might find that this is your best option right now!