Experienced centre-back Kevin Burgess, 32, joined the club from Scarborough and has also played for Whitby Town and Darlington.
Attacking midfielder Lewis Maloney and striker Louis Johnson complete the trio.
Maloney, 25, made 27 appearances last season after joining from Gateshead and is a Middlesbrough academy graduate.
Johnson, 22, came through the youth system at Newcastle and scored 10 goals in 26 appearances in his debut season at Marske.
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