Thread and Needle for Holster and Belts

[Columbiar]

Need some advice on thread and needles for heavy leather bolsters and belts. I got some of the Tandy waxed thread and needles and have done some practice with them but they both seem kind of light for the job. 

[chiefjason]

I hand stitch with size 0 harness needles and 456 machine thread.  456 is smaller than the spooled wax thread but not as thin as most makers use.  I like the size since I do a lot of contrast stitch and want it to stand out a bit.  I get mine from Tippmann.

[carguy4471]

I am pretty darn new to leather but here is what I do know.

On my holsters I currently used waxed "thread" from tandy.  I saddle stitch with harness needles from tandy as well.  If the thread is a little light for you, tandy also sells waxed braided cord.  It is just a few hooks over from the waxed thread and they look nearly the same unless you look very close.  The braided cord is 2-3x as thick.  My holsters are two layers of 8-9 oz leather and the "thread" works great.  I could not tell you now it equats to machine thread size though.