Se trata de un capuchón que cubre el portalámpara
y en este caso particular, se hacen incluso de cera, para imitar velas.

Candle covers or candle sleeves are an inexpensive way to freshen up the looks of a antique or early style fixture or sconce whose original candle cover or candle sleeve may have suffered from age, dirt, or heat damage. In light of the fact that most paper and plastic candle covers naturally change color with age, it may be best that you replace all candle covers on a fixture when faced with replacing only one or two covers on a fixture that requires many.