Layerable

In addition, since weather can change, bring layerable clothing and a lightweight waterproof poncho.

Source: wiktionary

Choose durable, layerable clothes which go together, are easy to wash and look good without ironing.

Source: wiktionary

At substantial cost, the Army had replaced earlier models of boots that shredded quickly, and it had been issuing layerable clothing like the sort bought in civilian camping stores, which could wick moisture and adapt to varying climates.

Source: wiktionary