June 13 (Reuters) - Britain's Spectris ( SEPJF ) said on

Friday it has rejected a second takeover proposal from private

equity firm KKR, days after the scientific instruments maker

backed a possible competing $5 billion bid from Advent.

Spectris ( SEPJF ) did not provide details on KKR's proposal, noting

only that it was the second proposal by the PE firm it had

rejected.

The company, which provides hardware and software solutions

to sectors such as pharmaceuticals, steel and automotive, said

on Monday it would accept private equity firm Advent's proposal

of 37.63 pounds per share if a formal offer was made.

Advent and KKR did not immediately respond to Reuters'

requests for comment. The competing proposal by KKR was first

reported by the Wall Street Journal on Friday.

Spectris ( SEPJF ) is the largest takeover target this year in

Britain, a country that has attracted overseas buyers in recent

years due to relatively cheap valuations.

Under UK takeover rules, KKR has until July 11 to make a

formal offer or walk away.