There are a few things to consider when purchasing knee pads. First, you need to measure the circumference of your thigh just above your knee. Second, you need to decide what type of activity you will be using the knee pads for. Third, consider what level of protection you need. Finally, take into account the climate you'll be wearing them in - hot or cold weather can affect how comfortable the pads are.
Once you have those measurements, it's time to start looking at different types and brands of knee pads. There are three main types of knee pads: Slip-on, sleeve and hinged. Each has their own benefits and drawbacks, so it's important to choose the right one for your needs. For example, slip-on pads are easy to put on and take off but don't offer as much support as hinged ones. Sleeve pads provide more support but can be uncomfortable in hot weather. Hinged knee pads offer the most support but can be difficult to put on if you have large thighs.
When choosing a brand, it's important to read reviews from other athletes who have used the product before making a decision. You also want to make sure that the company offers a good warranty in case there are any issues with the product down the line. With all these factors in mind, you should be able to find the perfect pair of knee pads for your needs!