Acredito que seja um TYPO, o nome correto são "muflas".

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Note added at 1 hr (2017-01-21 22:25:41 GMT)
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Se for mufla mesmo, outra alternativa é INSULATORS.

Typically, the metals are joined together via a special connector. Stripped wire (often stranded) is inserted through the correctly sized opening of the connector, and a crimper is used to tightly squeeze the opening against the wire. Depending on the type of connector used, it may be attached to a metal plate by a separate screw or bolt or it could be simply screwed on using the connector itself to make the attachment like an F connector.
Obtaining a good crimp requires using carefully engineered crimp tools and crimp connectors, and following the procedures specified by the manufactures. Examples of these procedures can be obtained from Molex,[1] TE Connectivity,[2] and other similar companies.

https://en.wikipedia.org/wiki/Crimp_(joining)

Portuguese term (edited): muflas

Também apostando em um typo...

muflas = terminações:
http://www.mdpolicabos.com.br/cabos_terminacao.asp

cable termination:
http://www.cable-jointing.com/heat-shrink-termination-kits-1...

muflas:
https://www.google.com.br/search?biw=1366&bih=631&tbm=isch&s...

cable termination:
https://www.google.com.br/search?biw=1366&bih=631&tbm=isch&s...


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Note added at 16 hrs (2017-01-22 13:20:17 GMT)
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https://www.google.com.br/url?q=http://www.copel.com/hpcopel...

"Terminação ou Mufla: Material cuja função principal é propiciar o alívio de campo elétrico e a transição entre... "

https://en.wikipedia.org/wiki/Ruffles