SP-44 Kester Soldering Paste Flux SP-44 is a paste version of Kester 1544 Activated
Rosin Flux. This formula makes an ideal bench top flux for touch-up and
soldering of electronic assemblies. The residue after soldering was found to be
non-corrosive after 48 hours at 120°F temperature and 85% humidity. However,
due to the softness of the residue, it is recommended that the residue be
removed with Kester 5240 Rosin Residue Remover.