The Chip Quik No-Clean Liquid Flux Pen is great for all rework, solder, de-solder, and reflow applications! In particular this one is from the rework-champs at Chip Quik.

Liquid flux helps solder to "cling" to metal by removing oxide buildup. It also helps spread out solder by reducing surface tension. Liquid flux is crucial for surface mount soldering and desoldering, but usually not necessary for through-hole components. With a pen, you can just 'draw' it onto the area you're working. 

Flux is a cleaning fluid, so use care and ventilation when in use!

• Flux Type: No-Clean Liquid Flux (for Leaded and Lead-Free applications)
• Flux Classification: INM0
• Packaging: Pen 10ml (0.34oz)
• Shelf Life
  • Refrigerated >24 months, unrefrigerated >24 months
• Storage and Handling
• Store refrigerated or at room temperature 3-25C (37-77F). The liquid flux can be allowed to freeze. Freezing will not degrade this product. Allow 4 hours for liquid flux to reach an operating temperature of 20-25C (68-77F) before use.