Randy Sun CORE Waterproof Ankle

Ankle. Cushion not published.

ankle · no height published, drawn at a typical heightpadding: the maker doesn’t say where · Waterproof membrane

The footwear outline is schematic. Check the cuff with your own shoes.

When you want a waterproof membrane for wet trails

An ankle waterproof sock with an inner layer of 66% coolmax polyester.

Keep in mind: Water can still get in over the cuff, and the three layers take more room than a standard sock, so try it in your shoes before a wet trip. The low cuff sits below a boot collar, so it suits trail shoes and low hikers rather than boots.

Closest in Randy Sun’s range: the THERMO Merino Waterproof. They differ in cuff and blend; the size chart is the same.

This sockTHERMO Merino Waterproof
CuffankleNot published
BlendSeparate blends for each layerSeparate blends for each layer

Compare the two side by side

Materials, padding and sock type

Waterproof membrane · cushion not published

None
Light
Full
Extra
Padding shown schematically. Brand labels do not share a thickness scale.
Exact model
Randy Sun CORE Waterproof Ankle
Style number
RS242 / RS272
Size chart
Unisex chart
Cuff height
ankle
Weight (maker’s term)
Not published
Cushion (maker’s term)
Not published
Cushion location
Not published
Sock type
Waterproof membrane
Layers
3
Material blend
Separate blends for each layer
Wool-free
Yes, no wool or alpaca listed
Facts from
Randy Sun’s US site

Inner: 66% coolmax polyester, 30% polyester, 4% elastane.

Outer: 61% nylon, 32% polyester, 7% elastane.

Between the inner and outer knits sits the middle layer of Randy Sun’s DROPZERO system, printed as a 100% PU membrane, PFAS free.

What Randy Sun says about it

“Its durable outer layer and moisture-wicking inner layer make it a dependable choice for hiking, trekking, outdoor sports, and everyday adventures.”

“High-performance nylon provides excellent abrasion resistance for lasting durability.”

“A waterproof-breathable membrane blocks water while allowing moisture vapor to escape.”

The maker’s own words from its product page; not tested by HikingSocks.guide.

Cushion and weight labels are this brand’s own terms. They are not a shared thickness or temperature rating.

XS
S
M
L
4.56810121415.5

US men’s

Bands follow this chart’s published ranges. XS: 4.5–6.5 · S: 7–10 · M: 10.5–13 · L: 13.5–15.5

Check the size and the shoe together

Start with the unisex chart for this exact model. Use the size lookup or the whole Randy Sun size chart to find the published range, then check the heel position, toe room and cuff in your footwear.

The maker does not give a heel-to-cuff measurement. Try the socks with your boots to see whether the cuff sits above the collar. See how sock heights differ.

Try the complete layered construction, not only one layer. Extra fabric can change toe room and pressure inside the shoe. The footwear-fit checklist explains what to check.

Care for the exact pair

Machine Washable: Turn inside out. Wash on a gentle cycle below 40°C (104°F). Use standard liquid detergent; avoid fabric softeners or bleach. Hand Wash: Gently rinse under lukewarm water to remove mud or sand. Do not wring or twist excessively. Gently press out excess water. Drying Protocol: Drip dry naturally in a well-ventilated, shaded space. Do not tumble dry, iron, or dry clean. High heat is the enemy of waterproof membranes.

Use the care lookup for this model’s wash and dry directions. A general wool routine should not override instructions for a membrane, a two-layer construction or a specific treatment.

Two socks to compare with it

Same size chart

Randy Sun FLEX Waterproof Mid Calf

mid calf · not specified. Your Randy Sun size carries over.

Compare side by side

Same cuff height

DexShell Running Lite 2.0 Waterproof Over the ankle

DexShell · over the ankle · not specified.

Compare side by side

Find similar socks

Product sources

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