Hijaz, belted Jambiya
 

Hi, This appears old the sheath shape is more like Saudi to me. The blade shape
is almost Shibriya like With a crudely made fuller. The wooden insert is snug and has an odd inner shape. I was thinking maybe a side knife? or Boys? Belt is for 34inch waist. Sheath seems small 7X51/2 inches. The blade is 61/2 inches by 1 3/4inches wide. Your thoughts on it. Thank you for your comments, Steve

My pick would be probably Yemeni.
Regards Stu

I disagree with Stu I think It is Saudi the belt looks to be all leather and the scabbard does not look Yemeni either more a mix of Saudi and maybe Omani without the rings? Funny how the blade has a rather crude fuller and not a raised rib this is definitely not a Yemeni trait.

Yes it is actually a very strange combination of Shibriyya blade with the scabbard from somewhere else. My thinking towards Yemen was based on the "meccan almost" hilt, with what seems to be a scabbard, with at least the silver?? being decorated with nails in Yemeni style. The belt style looks to be Saudi. Hopefully Steve will come in on this if he is not already on the way to Timonium.
Attached pic is of a Yemeni dagger with a similar style hilt.

Number 6 Combo
 

Hi Lew and Stu, The belt is all leather my main reference is Oriental Arms lists,
they consider them to be Wahabi ( Hijaz). I also felt the sheath was a slimmed down version ala Oman,without the rings. Stu, the hilt has some resemblance to your photo, but, this ones very used. Is it possible this a generational piece that reflects migration to other Arabic areas? That might explain the crude fuller to mimic a raised ridge on an existing blade. What do you make of the mail like sheath over attachment? Thanks again, Steve

The belt style certainly is similar to the belts on some Hijazi Dharia type daggers, and other saudi daggers, but there the resemblance ends in my opinion.
As I said before I would hope that Steve Gracie comes in on this thread, as he is very knowledgeable on arabian daggers
Regards Stu