The difference between the squares of two consecutive odd integers is always divisible by ?

Let the two consecutive odd integers be (2x + 1) and (2x + 3)
Then,

(2x + 3)² - (2x + 1)²

= (2x + 3 + 2x + 1) (2x + 3 - 2x - 1)

= (4x + 4)(2)
= 8 (x + 1), which is always divisible by 8