Product Data Sheet – SPOTCHECK SKL-SP2

Solvent-Removable Visible Penetrant

SPOTCHECK® SKL-SP2 is a solvent-removable visible penetrant designed for portability, especially for welding operations, and is post-emulsifiable for greater resolution of flaw indications. It produces a visible red colour contrast, and features outstanding penetrating characteristics.

SKL-SP2 is highly reliable at locating surface-open flaws and discontinuities, and can be used on non-porous ceramics and similar materials.

Chemical product icon - visible penetrant


  • Outstanding penetrating characteristics
  • Vivid, high-contrast color
  • Superior flaw resolution
  • Excellent reliability
  • Wide range of applications


Defect location: open to surface

Ideal for:

  • Castings
  • Forgings
  • Welds
  • Pressure vessels
  • Tubular goods
  • General metal work
  • Leak testing
  • Use in power plants
  • Construction applications.

Defect examples: cracks and leaks

NOTE: we do not recommend SKL-SP2 for inspecting plastic materials, as it may stain, soften or even dissolve the base material under test.

Specification Compliance

  • AMS2644
  • ASME B & PV Code, Sec V
  • ASTM D129
  • ASTM E165/E165M-18
  • ASTM E1417/E1417M
  • EN ISO 3452-1
  • EN ISO 3452-2 (Sensitivity Level 2)
  • MIL-STD-2132D
  • MIL-STD-271F


A blend of petroleum distillates, plasticiser and an oil-soluble organic red dye.

Product Properties

Form and colour Red liquid
Flash point > 93°C (bulk product)
Density 0.85 g/cm³
Corrosion Meets AMS 2644
Viscosity 3.8 mm²/s
Sulphur content < 300 ppm
Chloride content < 300 ppm
AMS 2644 class Type 2, Method B/C/D

Like all Magnaflux materials, our visible penetrants are closely controlled to ensure batch-to-batch consistency, optimum process control and inspection reliability.

User Recommendations

NDT Method Penetrant Testing, Visible
Storage temperature 10°C to 30°C
Usage temperature 5°C to 55°C (bulk);  -5°C to 50°C (aerosol)
Coverage 10 – 15m² per 400ml aerosol; 20 – 30m² per litre
Cleaner/remover SKC-S
Hydrophilic emulsifier ZR-10C
Solvent-based developer SKD-S2
Water-based developer ZP-5B
Accessories Reference test block (part no. 070C001)

Instructions for Use

Ensure test part is clean and dry, and free from oil, grease and other contaminants.

Apply penetrant by immersion dip, brush, flow on, conventional or electrostatic spray. Cover the test area completely.

Allow penetration time. Minimum penetration time is 2 to 5 minutes, with 10 minutes being adequate for most situations. Lower temperatures thicken the penetrant and require longer penetration times.

Remove excess surface penetrant with a solvent wipe or by the hydrophilic remover method (see opposite).

Apply a thin layer of developer* to the surface and allow a minimum of 10 minutes development time before inspecting the component under white light. Indications will appear dark red against the white developer background.

* A developer is used to maximise sensitivity and provide a white contrasting background. Two types of developer can be used:

  • Solvent-based: quick-drying materials which are applied by spraying. The component under test must be dry before developer is applied.
  • Water-based (aqueous): can be applied by dipping or spraying. To maximise penetrant sensitivity, parts should only be exposed to aqueous developers for short periods of time. The component must be dried before inspection.

Developer residue can be removed either by wiping with a cloth or by a water and detergent wash. Penetrant residues can be removed by vapour degreasing or solvent soak.

Solvent wipe method

Apply penetrant SKL-SP2 to the clean component and allow contact time.

Wipe off excess penetrant with a cloth dampened with cleaner/remover SKC-S.

Dry component, apply developer (SKD-S2 or ZP-5B) and inspect.

Hydrophilic method

Apply penetrant SKL-SP2 to the clean component and allow contact time.

Spray component with water to remove excess penetrant.

Immerse component in hydrophilic remover ZR-10C for the predetermined time.

Spray component with water to remove last traces of penetrant.

Dry component, apply developer (SKD-S2 or ZP-5B) and inspect.

Packaging and Part Numbers

Part number 008A016
x 10

Packaging icon: 400 ml aerosol can

Part number 055C076
x 4

Packaging icon: 5 litre metal can

SPOTCHECK® SK-3 Penetrant Inspection Kit (part number 008A038)

The SK-3 Kit is a portable visible penetrant inspection kit that includes the following:

  • 2 x 400 ml aerosol cans of SKL-SP2 penetrant
  • 3 x 400 ml aerosol cans of SKC-S cleaner
  • 3 x 400 ml aerosol cans of SKD-S2 developer
  • 1 cloth
  • 1 set of instructions
  • 1 portable carrying case (on its own: part number 053C009)

Health & Safety

Review all relevant health and safety information before using this product. For complete health and safety information, refer to the relevant Safety Data Sheet.

Download this Product Data Sheet as a PDF