DC disconnect switches.
Rated 450V, and you measured 435V.
I might want a 600V switch especially if installing for someone else, but for my own place I'd probably turn it on and use it.
Would only exceed 450V on a cold day. Normally when switch turned off, it has Voc on PV side, and Vmp on capacitors of inverter, so not breaking much voltage. (If there was a short circuit, that is when it would see Voc across it, 435 under today's conditions up to maybe 525 or 550V in very cold weather.)