two 2 x barlows = one 4 x barlow?

[PSALM19.1]

Hi, wondering, does stacking two 2 x barlow's yeild the same magnification as one 4 x? (Borrowed a 4 x off a friend of mine and used on my 8" Dob and couldn't focus down with it; yet using the double 2 x method works quite well).....thanks:question:

[Merlin66]

Basically yes.
You can get the same amplification ( ie x2 to x4) by doubling the distance (spacer?) behind the barlow.

[PSALM19.1]

Thanks Ken; read somewhere, sometime on google that two 2 x barlows only yields around 3.5 times...??? Can't always trust MrGoogle! Thanks again!