SuperBlur Background Kit
SuperBlur is a PNG & PSD background kit that features countless graphical blur designs and options. Included are 28 .PNGs, each with a different blur variation. The .PSD (Photoshop document) includes many dozens of layers of blur elements and textures, which you can mix and match to create hundreds of different variants.
Photoshop isn't required for this pack, as it does include more than two dozen (28 to be precise, as mentioned above) .PNGs. If you do use Photoshop, though, you'll have the advantage of being able to manipulate and work with each blur group to create a style of blur to your liking.
This kit is designed in 4K resolution (4096 x 3112 pixels) with 300 DPI, so there's a vast amount of detail and can be used in very high resolution projects.