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Dryalite Headlight Moisture-Fix Kit | BMW 4 Series F32/F33/F36 (2013-20) (pair)

Dryalite absorbs humidity from the air inside your headlight. Choose your vehicle to find the right kit.

Kit: £50.00 - Available.

Dryalite Headlight Moisture-Fix Kit | BMW 4 Series F32/F33/F36 (2013-20) (pair)

Fitment and specification

Dryalite Headlight Moisture-Fix Kit (Pair)
Fits: BMW 4 Series F32 / F33 / F36 with removable twist-off dust caps
✓ Helps reduce internal headlight condensation over time
✓ Quick DIY install (typically under 2 minutes)
✓ Reusable desiccant if moisture returns
✓ Helps protect expensive headlights (often £1,000+ each to replace)
Compatibility
This kit is for BMW 4 Series F32 / F33 / F36 headlights that use a hand-removable twist-off rear dust cap.
Dust cap part number (moulded on the cap): 305 239 308
(May also appear without spaces as 1305239308 depending on how it’s written.)
Best way to confirm: remove your existing cap and check the number + compare the shape to the fitment photo. If you’re unsure, message me a photo of your cap and I’ll help confirm before you buy.
Not compatible
This kit will not fit if:
  • Your headlight has non-removable / sealed caps (no twist-off access caps)
  • Your cap has a different part number 
What’s Included
  • 2 × Dryalite Moisture-Fix Caps (left + right)
  • 2 × 50g silica gel desiccant packs
Installation (no tools)
  1. Open the bonnet and locate the top access dust cap on the headlight.
  2. Twist the original cap off by hand.
  3. Fit the Dryalite cap in its place.
  4. the desiccant will absorb moisture over time.
Notes (Please Read)
  • This kit is intended for condensation / humidity issues. If there is standing water, a cracked lens, or damaged seals, the underlying leak should be repaired first.
  • Not all BMW 4 Series headlights use the same cap  fitment is based on the dust cap part number and a visual match, not model year alone.
Re-activating the Desiccant
Microwave: 3–5 minutes at 700W.
Oven: 30–60 minutes at 100–120°C.
30-day money-back guarantee

How does Dryalite reduce condensation?

Dryalite holds moisture-absorbing silica gel inside vehicle-specific headlight caps. It absorbs water vapour from the air inside the headlight, leaving less moisture available to condense on the lens.

Twist-off cap kits need no cutting or drilling. The sealed-cap F10 kit uses a different fitting method explained in its product details.

Recurring misting, not active leaks. If the headlight is cracked or has pools of water inside, Dryalite will not fix it. Repair the fault first.

Green means recharge.

Remove the silica packets, dry them until the beads turn orange, let them cool, then put them back.

30-day full-refund guarantee

If it does not help, return your kit within 30 days for a full refund.

Questions before ordering.

Will Dryalite fix every condensation problem?

No. Dryalite absorbs humidity from the air inside the headlight. It cannot repair a cracked headlight or deal with pools of water inside it.

Is the silica gel loose inside the headlight?

No. The silica packets sit securely inside the Dryalite cap, away from the bulb and reflector.

How quickly should I see a difference?

Some buyers see an improvement within hours. Allow a few days, as every headlight starts with a different amount of moisture.

Can I dry my headlights with a hairdryer before fitting Dryalite?

Warming a headlight can clear visible mist temporarily, but it does not necessarily remove the moisture: droplets may simply turn back into water vapour. If you choose to use a hairdryer, follow your vehicle manufacturer’s guidance and avoid high heat, which can damage plastic, seals or electronics. Let the headlight and the air inside cool to ambient temperature in a clean, dry, sheltered place before refitting the caps. Warm air can contain more water vapour before condensation forms; if warm, moist air is trapped inside, misting can return as the lens cools. Cooling alone does not remove moisture. Dryalite absorbs water vapour to help lower humidity after fitting.

Why use Dryalite instead of leaving the dust caps off?

Removing a dust cap may help moisture escape temporarily, but leaving it off also exposes the headlight to dust, debris and water splashes. It does not actively absorb moisture, and damp outside air can enter again. A correctly fitted Dryalite cap with an intact seal keeps the access opening covered while silica gel absorbs water vapour inside. This helps manage humidity while keeping debris out, rather than leaving the headlight open. Keep the headlight’s original ventilation paths clear, and repair damaged housings or seals first.

How do I choose the right kit?

Choose your model above and compare the product photos with your headlight cap. Contact us if you want help checking.

Can the silica gel be reused?

Yes. Orange means ready and green means saturated. When the beads turn green, remove and dry the silica packets, let them cool fully, then refit them. Never heat the caps or seals.

Do I need to permanently modify my headlights?

Twist-off cap kits require no permanent modification. The sealed-cap F10 kit uses a different fitting method, so check its product details before ordering.

How often will the silica need recharging?

It depends on the weather and your headlight. Check the indicator beads and recharge only when they turn green.

What if Dryalite does not help?

Return the kit within 30 days for a full refund.