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Amber rosin paste flux in 2oz jar

SRA 135 Rosin Paste Soldering Flux 2oz 56.6g

SKU CH-F6N7-A8XE0

Rosin-activated paste flux for lead and lead-free soldering on circuit boards and copper wire, active from 93 to 315 °C, supplied in a 56.6 g jar

  • Certifications and standardsLead Free Compliant
  • USA-made quality flux for reliable solder joints
  • Semi-solid paste consistency gives precise application control
  • Acid-free formula safe for electrical and electronic work
  • Active temperature range 93–315 °C / 200–600 °F
  • Lead-free compliant rosin-activated flux for modern assemblies

SRA 135 Rosin Paste Flux 2oz Jar

SRA 135 is a petrolatum-based rosin paste flux designed for electrical and electronic soldering tasks. It contains rosin and organic acid activators without zinc chloride or ammonium chloride, making it suitable for lead and lead-free alloys. The 56.6g jar provides a semi-solid consistency that allows controlled application by dipping wires or brushing onto PCB pads.

Active Temperature Range 93 to 315 Celsius

This type RA flux activates between 93 and 315°C (200 to 600°F), so the joint must reach that window for the activator to clean oxides and promote wetting. Below the lower limit the flux will not flow properly, while exceeding the upper limit risks burning off the rosin before solder melts. The residue is non-conductive and non-corrosive, so cleaning is optional for most electronic assemblies.

Semi-Solid Consistency For Dipping Wires

The amber paste holds its shape in the jar yet yields easily to a wire tip or brush, preventing the runny mess common with softer fluxes. Crystallisation on the surface is normal and does not indicate degradation. Because the formula leaves a protective rosin coating, the joint resists oxidation during storage, and the wide-mouth container allows repeated access without contamination.

How it compares

Measured against everything we stock in Soldering Irons & Stations, at today’s prices. Recalculated every night.

Price $14.99
Cheaper than about 73% of the 802 comparable items (median $25.99).

Specifications

Environment & compliance
Certifications and standardsLead Free Compliant

Questions about this item

Which jar size is offered for this flux?

This listing provides a single 2oz jar weighing 56.6g, so there are no alternative capacities to choose from.

What does the active temperature range of 93–315°C mean when I am soldering?

The flux activates at 93°C and remains effective up to 315°C, covering typical lead and lead-free solder melting points so the solder flows cleanly across that whole window.

What type of flux is SRA 135 and what residue does it leave?

It is a type RA rosin-activated, petrolatum-based paste that leaves a safe, non-corrosive residue which can remain on the board without cleaning.

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