A few hours; several hours — an approximate duration measured in hours (e.g., two or three hours).
会議は数時間に及び、結論は出なかった。
The meeting lasted several hours and no conclusion was reached.
渋滞で到着が数時間遅れると言われた。
I was told arrival would be delayed by a few hours due to traffic.
その作業は数時間かかるから、休憩をとって進めよう。
That task will take a few hours, so let's take a break and then continue.