303 Aerospace Protectant vs Waterproofing Wax for Leather: which is safer?

Nikwax Waterproofing Wax for Leather is our pick: better on PFAS and on the overall hazard picture.

303 Aerospace Protectant

303 Protectant

303 Aerospace Protectant

PFAS grade

Poor 40/100

Overall grade

Bad 0/100

Verdict

Skip

Hazard flags

⚑ 5

Material

Silicone-based protectant with UV inhibitors and water repellent coating

Confidence

45%

PossibleVolatile organic compounds (VOCs) from spray carrier

PossibleSiloxane polymer bioaccumulation

ReportedSurface slipperiness hazard

Our pick

Nikwax Waterproofing Wax for Leather

Nikwax

Waterproofing Wax for Leather

PFAS grade

Good 65/100

Overall grade

Good 51/100

Verdict

Skip

Hazard flags

⚑ 2

Material

wax-based waterproofing

Confidence

78%

PossibleRespiratory irritation or fume inhalation during application

ReportedPFAS in water repellency treatment

Where these two actually differ

  • We flag Volatile organic compounds (VOCs) from spray carrier, Siloxane polymer bioaccumulation, Surface slipperiness hazard and Lack of ingredient transparency for UV inhibitors and slip agents on the 303 Protectant and not on the Nikwax.
  • We flag Respiratory irritation or fume inhalation during application and PFAS in water repellency treatment on the Nikwax and not on the 303 Protectant.
  • The 303 Protectant is Silicone-based protectant with UV inhibitors and water repellent coating where the Nikwax is wax-based waterproofing, which is most of the difference in these two grades.
  • The gap is 25 points, wide enough that this is not a close call, and the Nikwax is the one to buy.
  • We are less certain about the 303 Protectant grade, at 45% confidence against 78%, because it discloses less.

Both products run through the same public rubric: materials, coatings, brand disclosure, lab findings, and recalls, plus a beyond-PFAS hazard analysis. Grades are model-based estimates, not lab tests. How grades work →

More fabric stain guard sprays: see the full ranking