Good to know for the ADJ. So they would be serviceable, but I would guess most hobbyist soldering irons would have a hard time desoldering the heavy contacts on the relays without damaging the board.The internal relays on the ADJ strip are the same brand and family of relays that are on the 8 channel relay boards. They are Songle branded SRD relays. The 8 channel boards are 5v relays, and the ADJ strip are 12v relays. Both are rated at 10amps at 250V, meaning for longevity running them under 5 amps is wise.
Here is the SRD family datasheet
https://www.google.com/url?sa=t&sou...FjAAegQIAhAB&usg=AOvVaw1jp0lAaqaJ9gb15aqbN-6t
So for a low load (~1-2Amps) and an interval of 30seconds on operations , the MTBF should be in the 3-5 year range.