Using the Chip Quik No - Clean Liquid Flux Pen is easy. Just 'draw' the flux onto the area you're working on. It's great for soldering, desoldering, and reflow jobs. Remember, flux is a cleaning fluid, so make sure you use it in a well - ventilated area. You can store this pen either in the fridge or at room temperature between 3 - 25C (37 - 77F). It can even be frozen, and it won't get damaged. But before you use it, let it sit for 4 hours to reach a temperature of 20 - 25C (68 - 77F). It has a long shelf life of over 24 months, whether refrigerated or not. If you prefer using a syringe, we also have a liquid tacky flux option.