This refers to how the airbrush functions. With single action only the air is controlled with the trigger. The trigger will control the air and the amount of paint that comes out is determined by the needle adjustment on the back of the airbrush handle. Dual action is when the trigger on the airbrush controls both the air and paint. Also washing the material will take care of any shrinking prior to placing your airbrush art design on to the material. So make sure that you have washed and fully dried your material before you begin. Leather needs to be wiped down with rubbing alcohol prior to doing any airbrushing. This will remove the oil that is on the leather. Another great way if you are doing this at home is to allow the design to dry then turn the shirt inside out and throw it into the dryer for about 40 to 45 minutes on the highest heat setting. After this your design will hold up to laundering. If you use a paint that does not require heat setting then you should still set the design. When it comes to any part of your actual airbrush equipment such as the airbrush and its parts as well as the compressor make sure to go with name brand. Do not use any knock offs a these will cost you more money and lots of headaches in the long run. You get what you pay for and when it comes to airbrush art you need to go with names that you can trust. The starter kit also give you 50 Vynalaser stencils that can be reused over and over again. Airbrush Bodyart's starter kit runs around $293. Individually all the same products that you get in the kit, would run you around $346. If you want to step your airbrush kit up then Airbrush Bodyart offers a professional kit. She is recognized among her peers and airbrush enthusiasts for your custom airbrush art. Her surfaces choices for her airbrush art include automotive and motorcycles and the body. It is her airbrush art on the motorcycles that has placed her in the ranks with other famous custom airbrush artists. Her airbrush art has been featured in the 2006 Iwata, the RM 2006 and the 2007 Paint calendars.