John Gill Commentary 2 Kings 10:2

"And now as soon as this letter cometh to you, seeing your master`s sons are with you, and there are with you chariots and horses, a fortified city also, and armor;" — 2 Kings 10:2 (ASV)

Now as soon as this letter comes to you, seeing your master's
sons are with you
Sons of Ahab, and some of Joram, and all either the sons or grandsons of Ahab:

and there are with you chariots and horses
military ones:

a fenced city also
as Samaria was, well walled and fortified, and able to hold out a long siege:

and armour
of all sorts, to arm themselves and people with in their defence.