Regarding your main question at the start of the thread - nearly all M.2 drives in the retail market are 2280 size, and if no size is given in a retail listing for an M.2 drive, it's highly likely to be 2280.  2242 drives tend to be OEM drives used in laptops or small form factor computers.  2260 and 22110 drives are rarer form factors still....

m.2nvme

Post the deets with THIS TUTORIAL.  You will be copying the LINK to your Clipboard, which is virtual, so right after you need to Paste it into your next post.

What does 2242 or 2280 form factor mean? I plan on getting a second internal drive, I am worried I will buy the wrong SSD. Does the packaging make it obvious at the store?

m.2sata

It is a bit unclear, but here is what I think having looked at the manual.  The diagrams for the 2242 and 2280 drives both appear to be at the exact same location on the motherboard.  This suggests there is only one M.2 slot for SSD's, which may be supplied by Lenovo factory fitted with either a 2242 or 2280 drive depending on system configuration.  In other words it suggests the system will accommodate either a 2280 or a 2242 drive, but not both.  Asking Lenovo directly may clarify whether this is the case.

Post the deets with THIS TUTORIAL.  You will be copying the LINK to your Clipboard, which is virtual, so right after you need to Paste it into your next post.

Did you try googling it?   "Form Factor" when used about drives means the physical size of the drive.   Yes, with an M2 SSD you should be able to see the difference in the lengths, but maybe not if it's in a box.

M 2 form factorsreddit

From the pictures in the Users Guide it looks like they are just showing you that the longer M.2 slot can accommodate a shorter M.2.

m.2ssd

As I said most MB (until very recently) only had one NVME M.2 2280 slot, Laptops often have an additional  PCIe 2242 M.2 for Wifi\Cell\Bluetooth.

Most Systems also have around 6 SATA ports which take the standard "SSD" meaning it's a 3.5 or 2.5 device which is the electronic replacements for what use to be spinning platter hard drives. SATA ports are also for CD\DVD drives.

M 2 form factorsnvme

If this is correct, if the M.2. slot is already populated in your system, you should still be able to fit a 2.5" SATA SSD as a secondary drive.

m.2e key

Else - Do as PCPunk suggests Go get a 2.5 Drive (SSD or HDD)  or a 3.5 HDD (whatever your case fits).  A 3.5 HDD has larger sizes available and less cost per MB.

My concern is most systems have 1 M.2 slot. depending on the slot's "Key" (or notch, B or M) it could require either a "NVME M.2" or a "SATA M.2"

Here is an example of a Sabrent 2242 drive on Amazon (note they specifically state it's a 2242 size) - https://www.amazon.co.uk/dp/B07XVTRFF8

m.2vs nvme

It came shipped with a 500 GB SDD, it's my boot drive, and from your replies it appears if I want to add an additional much larger SDD it won't be possible as there is a fixed cap at 512GB and the slot is occupied. I was after 1TB-2TB for a second operating system. I am after speed and don't mind a second heat sink. Is 2.5" SATA SSD as a secondary drive the way to go?

m.2sizes

The M.2 SSDs come in three specific sizes – 2242, 2260 and 2280. Well, the nomenclature is what would represent the dimensions of the drives. The first two digits represent the width of the drives, while the last two figures are representative of the length. The M.2 2242 merely the diameter of 22 mm and a length of 42 mm. Likewise, the M.2 2260 and M.2 2280 come with the measurements of 22 mm width and 60 mm length and 22 mm width and 80 mm in length. The width for the drives is uniform across all of them with a difference in the range.

EDIT - Just a thought, but with such a question are you sure that you need an M2 SSD and not a SATA SSD? Which you need will depend on your computer/motherboard.

Heatsinks are generally optional on M.2 drives, although recommended.  On most drives, simply having enough air flow over the drive will keep it cool enough most of the time, but you can get various aftermarket coolers which can be attached.

The number you've quoted only seems to lead back to one of your other topics on here, where you state you have a Lenovo IdeaCentre 3 07IMB05.  With some further digging I found the manual for that Lenovo computer.

Also - If you have only one M.2 slot and the current device contains the OS, Swapping it requires additional steps and backup\recovery tools.

We are 15 responses into this thread with multiple people trying to help you and your inability to follow simple directions and provide us with any useful information to direct you is frustrating....

If the board also has a small 2242 slot that is typically for short Wifi or Bluetooth cards and if there aren't holes on the MB to move the post back then it's only a 2242.

You can install One NVMe SSD and I would go with the 2280 as that is the current standard.  While the specs don't tell you this, you should also be able to install a SATA M.2 SSD if you wanted as that will fit in the NVMe Slot.  The SATA will be a little slower but if you can get a good price on one that may be good for you.  You don't need a heatsink unless you want full performance for large file transfers.  During small file transfers the drive won't get hot enough to degrade performance, but larger files it may.  The heatsink will allow the drive to work longer before throttling back due to heat.

You currently have javascript disabled. Several functions may not work. Please re-enable javascript to access full functionality.

Would any one of those fit inside regardless which one I bought? I already have one slot in my desktop that's SSD, and my intention was to get another SSD.