Assertion: small coil | /r/ObjectUse | used in recent years
Facets:
value: with a coil core
type: OTHER
value: with other core types
type: OTHER
Source sentences:
text: In recent years, small "micro-coils" are being used in the upholstery (comfort layer) of mattresses, primarily with a coil core ("coil-on-coil" construction), but sometimes with other core types.