Soldering fluxes for OSP soldering OSPI 3311M Flux for soldering OSP new Interflux® OSPI 3311M is an alcohol based no-clean flux for soldering OSP finished boards that have passed one or more reflow cycles. OSPI 3311M provides optimised through hole fill on degraded OSP finishes. OSPI 3311 alcohol-based soldering flux outdated OSPI 3311 has been replaced by OSPI 3311M. Show all