KG's Heavy Duty Silicone Water & Stain Repellent vs Ultra- Sil Stuff Sack Set: which is safer?

Sea To Summit Ultra- Sil Stuff Sack Set is our pick: better on PFAS and on the overall hazard picture.

KG's Heavy Duty Silicone Water & Stain Repellent

Keen

KG's Heavy Duty Silicone Water & Stain Repellent

PFAS grade

F 25/100

Overall grade

F 13/100

Verdict

Skip

Hazard flags

⚑ 3

Material

silicone-based water and stain repellent coating on textile

Confidence

45%

PossibleUndisclosed coating additives (catalysts, surfactants, crosslinkers)

PossibleFormaldehyde resins in textile base or finishing

PossibleCoating degradation and microparticle shedding over time

Our pick

Sea To Summit Ultra- Sil Stuff Sack Set

Sea to Summit

Ultra- Sil Stuff Sack Set

PFAS grade

D 65/100

Overall grade

analysis pending

Verdict

pending

Hazard flags

none flagged

Material

Ultra-Sil nylon fabric, no water treatment applied

Confidence

78%

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 waterproof outdoor accessories: see the full ranking