De or het wandelkleding?

The correct Dutch article is:

de wandelkleding

Rule Words ending in -ing: almost always de. See the rule
Meaning (Dutch) functionele kleding die is ontworpen om comfort, bescherming en bewegingsvrijheid te bieden tijdens het wandelen, ongeacht de weersomstandigheden

How to use wandelkleding

the wandelkledingde wandelkleding
this wandelkledingdeze wandelkleding
that wandelkledingdie wandelkleding
our wandelkledingonze wandelkleding
your wandelkledingjouw wandelkleding
every wandelkledingelke wandelkleding
which wandelkleding?welke wandelkleding?
a big wandelkleding / the big wandelkledingeen grote wandelkleding, de grote wandelkleding

Meaning, plural, diminutive, pronunciation and translations: WikiWoordenboek (Dutch Wiktionary) (CC BY-SA 4.0). Example sentences: Tatoeba (CC BY 2.0 FR).