jmuller wrote:
are posible substitutes for SSS6n60?

I guess N-channel, 6A 600V. P6NB60 or STP6NB60 is the standard industry
number for such a MOSFET nowadays. I guess you could try a BUZ91,
IRFBC40, BUK457-600 or a BUK657-600, all having similair specs.

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Met vriendelijke groet,

Maarten Bakker.