I understand spinning hard drives are available in two thicknesses and most of what I found state...

[G+_Rud Dog]

I understand spinning hard drives are available in two thicknesses and most of what I found states 3.5 and 2.5 .071" and .037". (omitting laptop drives)

 

Can I safely order a 3.5" drive and have it fit in a slot specifically for that size drive. Don't want the thinner drive to flop about in the slot? Adapters are really not something I wish to muck around with so eliminating the use of these items.

[G+_Ben Reese]

All drives should have screw holes and your drive slots should have matching screw holes.

All the 2.5" drives I've installed have had matching screw hole patterns - regardless of thickness. I'd expect 3.5" drives to be the same. I'm pretty sure all the 3.5" drives I've seen have been the same thickness.

[G+_Black Merc]

3.5" drives are standardized on the old 3.5" floppy drive bays, 2.5" drives are the shrunken hdd standard for laptops.(lower power req. too).

The "thickness" of a hdd is not as standardized based on manufacturers designed components and number of platters(individual disks) that actually make up the hdd.

[G+_Rud Dog]

Maybe a bit more information is in order. There are slots in one of my very old Nas (Drobo) and they are set to accept the thicker drives. If I slide in a smaller in thickness drive it sits at an angle and I have to use a spacer whether it be pencil or wedge to get it to sit level. This is probably not the case with other NAS devices but don't know for sure.

The drob does not have any kind of sled to mount the drive into just slide the bare drive in and off you go. Probably due to the age of the unit don't know.

Does the Synology NAS use a adapter for all drives?

[G+_Black Merc]

I agree with Ben Reese ... Drive bays I've come across have had places for screws or come with guide rails(or something) to ensure that the drives stay in place.

[G+_Akira Yamanita]

What kind of slot are you talking about? A hot swappable bay for a NAS or something? I have seen low profile 3.5” drives. If the slot relies on the thickness of the drive, then it might not sit securely. e.g. The slot in my hard drive dock will not accommodate a low profile drive. It will fit, but won’t be held securely.

 

If it’s an internal drive bay in a PC case, then the mounting screws or rail kit will hold it in place without a problem.

[G+_Rud Dog]

Akira Yamanita Hot swappable drive in a NAS. When I order my drives I want to be sure I order the correct ones. The naming of drives on Amazon don't do a very good job of telling you what type drive you are buying other then 3.5. or 2.5, hence the question.

[G+_Akira Yamanita]

Unless otherwise specified, I think that it's safe to assume standard (approximately 1") height. If you want to be extra cautious, look up the spec sheet for the model.

 

What are the .071" and .037" measurements that you're referring to? WD and HGST specs say 1.028" (26.1 mm).

[G+_George Fromtulsa]

Pretty sure the Drobo site will provide specific answers for your model Drobo.

drobo.com - Choose Drive

[G+_Chris O'Riley]

The spec listings on most sites should indicate the exact dimensions of the drive. If you didn't want to use spacers, you could just limit yourself to models with the correct dimensions. If you couldn't find an exact fit, you could probably make up the difference by double-sided taping on material of some sort - maybe some long, thin Lego pieces or similiar. Wouldn't necessarily look pretty, but if it's a NAS, you put the drive in, close it up and forget about it for years.

[G+_Rud Dog]

Thank you all after reading the thoughts herein decided to order 3.5 drive and if the dimensions aren't correct will use it in my PC. Also will order 2.5 drive for use in my son's pc . Hopefully this will help with the lack of dimensions on placed like amazon.

[G+_Chris O'Riley]

Buying from Amazon doesn't preclude checking the specs on another site. Just search for the same model number on Newegg and it's bound to come up.