I got some 1 & 3/4" staples for my MFS111.

Can I use them for 3/4" flooring?

Do I need to use more of them than the 2" I normally use?

Thanks!

You'll be fine. No difference really. 1 1/2" staples are often used with plywood on concrete.

2" staples and fasteners are primarily made for 33/32 flooring, or when the substrate is greater then ¾.

You don't want the fasteners to pop through the subfloor/decking.

You loose holding power. More so over OSB, than plywood.

John Namba explained it much better then I did, when Mohawk said 2" was OK and popping through the subfloor was no concern. John set them straight. Tension withdrawal, is what he called it.

Better warn the millions of homes with hardwood floors and 2" staples in wood subfloors.

Yep, a squeaky floor over an unfinished basement or crawl space is a buzz killer, when 2" staples pop through especially over OSB.

The roofing industry has strict specs on this, with shingles.