Keep your favourite seamless pieces looking and feeling like new with our critical care tips.
Why Seamless Underwear Needs Special Care
Your FitKnicks seamless underwear isn't just regular underwear — it's a work of textile engineering. Those beautifully smooth, invisible lines you love are created using specialised fabrics and construction techniques that need a gentler touch than traditional underwear when it comes to washing.
Unlike conventional underwear with thick seams and robust stitching, seamless pieces rely on delicate bonding techniques and ultra-fine fibres to create that second-skin feel. This makes them more sensitive to heat, harsh chemicals, and rough treatment.
Special note for leakproof styles: Our leakproof underwear features bonded gussets that provide the absorbent protection you rely on. These bonded areas are particularly vulnerable to heat and aggressive washing because the heavier absorbent layers create additional tension on the bonds when exposed to hot water or rough wash cycles. Proper care is essential to maintain your leakproof protection.
Remember, a little extra TLC goes a long way in preserving your undies.
The Perfect Wash: Step-by-Step Instructions
Temperature: Keep it cool
Always wash at or below 30°C on a delicate cycle with low spin.
Why this matters: Heat is the enemy of seamless construction. Higher temperatures can weaken delicate bonding, leading to puckering, warping, or separation at the edges. Cool water cleans effectively while preserving the fabric’s integrity.
Critical for leakproof styles: This temperature rule is non-negotiable. The bonded gusset layers work together as a waterproof barrier, but hot water makes different materials expand at different rates, stressing the bonds. Even a single hot wash can begin to compromise the bonding.
Detergent: Choose wisely
Use only gentle, pH‑neutral detergents — no harsh chemicals.
The science: Our seamless fabrics contain elastane and nylon, aka. stretch fibres. Harsh, highly alkaline detergents can degrade these fibres over time, reducing stretch and comfort.
What to never use
No bleach (even colour-safe options can weaken fibres)
No fabric softener (leaves residue that reduces breathability and can irritate skin)
No dryer sheets (deposit waxy residues that compromise the fabric’s natural properties)
The mesh bag rule
A mesh wash bag is highly recommended for seamless pieces.
Your washer’s agitator and zippers/snags from other garments can catch or stretch seamless underwear. A mesh bag protects while allowing water and detergent to circulate freely.
Smart sorting
Do not wash seamless underwear with jeans, towels, or other bulky, rough-textured items.
Heavy items can crush delicate fabrics; rough textures can cause micro-tears or pilling. Wash with other delicates like bras and lightweight tops.
Drying
Air dry only
Always air dry your FitKnicks underwear — tumble drying is an absolute no‑no.
Even “low heat” dryers can damage elastic fibres and seamless bonds. Tumbling can also distort the engineered shape.
Location matters
Dry away from direct sunlight and heat sources (radiators, heaters).
UV can fade colours and weaken elastics; heat can cause similar damage over time. Choose a well‑ventilated indoor area or shaded spot.
Laying vs. hanging
Lay flat to dry when possible, or hang carefully by the waistband.
Laying flat best preserves shape. If hanging, use the reinforced waistband.
The Never-Ever List: What to Avoid
- No tumble dryers — air dry only.
- No fabric softeners — they leave residue and reduce breathability.
- No bleach — even colour-safe options can weaken fibres.
- No dryer sheets — they deposit waxy residues that compromise the fabric.
- No ironing — not even on low heat.
- No dry cleaning — the chemicals and techniques used can damage the materials and bonds.
- No rough handling when wet — don’t stretch, twist, or wring.
Extra care for leakproof gussets
Never stretch, twist, or wring the gusset area, especially when wet. The bonded layers are most vulnerable when saturated; aggressive handling can cause bonds to separate.
Troubleshooting: Common Care Questions
Remember: when you follow care instructions, none of the below issues should happen. If, however, your FitKnicks experience any of the below regardless of proper care it is critical to contact us as soon as possible so we can help rectify it. 😊
Q: Can I hand wash?
A: Absolutely — ideal for seamless, especially leakproof styles. Use cool water and gentle detergent. Avoid wringing; for leakproof gussets, gently press water out without stretching.
Q: How often should I wash?
A: Wash after each wear for hygiene and longevity. Seamless pieces are lightweight and quick-drying, so rotating multiple pairs helps — especially for leakproof styles.
Q: Small bumps or pilling appeared — what happened?
A: This usually results from washing with rough fabrics or skipping the mesh bag. While pilling can’t be fully reversed, you can prevent more by following the care guidelines.
Q: The elastic feels looser. Is that normal?
A: Some relaxation is normal over time. Premature loosening often comes from hot water or any form of machine drying. Stick to cool water and air drying to maximise elastic life.
Q: The bonding on my leakproof underwear is coming apart. Why?
A: Almost always heat-related — hot wash water or tumble drying. The multi-layer gusset creates extra tension as materials expand in heat, stressing bonds. Once separation starts, it tends to worsen with each wash. Cool water and air drying are key.
Q: Why is the leakproof gusset more sensitive?
A: The gusset has multiple bonded layers (absorbent core, waterproof barrier, comfort layer) that must work together. These materials expand/contract differently with heat, putting added stress on bonds.
Q: My underwear lost its shape. Can I fix it?
A: Once shape is lost due to improper care, it’s difficult to restore. Following the care instructions from day one prevents this.
Q: I accidentally used hot water once. Are they ruined?
A: Not necessarily, but bonds may be weakened. Inspect the gusset for separation or bubbling. If intact, return to cool-water care immediately; damage may appear after later washes.
Q: Why emphasise bonding for leakproof underwear?
A: Bonding failure is the most common and preventable cause of performance loss. Once the waterproof barrier’s bonds separate, it can’t be repaired. Prevention is the only way to maintain protection.
The Bottom Line: Care Equals Longevity
Treat caring for your FitKnicks seamless underwear as an investment in comfort, confidence, and value. Each time you follow these instructions, you preserve the engineering that delivers invisible smoothness, all‑day comfort, and long-lasting quality.
For leakproof styles: You’re also protecting the bonded gusset technology that provides leak protection. Once heat or rough handling damages these bonds, they can’t be restored — prevention is everything.
Your Care Commitment
By following these guidelines, your FitKnicks seamless underwear will maintain quality, comfort, and performance far longer than pieces that aren’t properly cared for. These aren’t just suggestions — they’re your roadmap to getting the most from your investment.
Still have care questions? Our customer service team is happy to help with specific queries. This guide helps maximise lifespan and performance throughout the intended wear period.