There are versions from 1 to 5. I could never tell you more than this web site!

https://rr.pokefinder.org/wiki/Super_Snapshot

I own and still use version 4, which is in the photos below!

Snapshot 64 was initial hardware that later turned into the Super Snapshot cartridge.
Goto this wiki to learn more than I could ever tell you.

Here is the MANUAL: Snapshot_64_Instruction_Manual
Here is the F-KEY Overlay: Snapshot_64_Function_Key_Overlay

Smart Cart claims to be able to copy all C64 programs AND cartridges.
Looks like this item would plug into your C64 and had a slot to be able to plug a cartridge into it also. Seems like this would be a very rare find if you have one.

The Shadow was sold my Megasoft in 1985-86. This was a hardware/software combination. Claiming a 99.9% effectiveness.There was also a GT Package that you would install in your 1541 to display the Track and Sector, very much like an Indus GT disk drive. Also added a reset switch and a device number change. I am not sure how you installed this.

From old Usenet postings it seems that there was questions on if this hardware actually worked or not.  Megasoft was rumored to spend $400,000 on advertising for this produce. Also rumored that Megasoft went out of business because of this? Can anyone confirm or deny these rumors?

9-2020 – More photos added sent to me from Craig Ernster – Thank you

THE SOFTWARE DIRECTORY:

The RAMBOard was a small card that you installed in your 1541 drive to be able to copy games that software only copiers couldn’t. Added more memory to your 1541 and worked with the Maverick copy software.
The installed photo is from ShadowM’s Commodore 64 Pages 

Here is the software disk that came with the RAMBOard: Ramboard D64 disk

ISEPIC was a Freeze cartridge released by Starpoint Software. Pronounced as Ice-Pick. I don’t think this was the first freeze cartridge, but it was one of the first. Again a ‘Freeze’ cartridge was great for by-passing start up copy protection. Basically you just wait until the program loads to the title or start screen and press the freeze button. The cartridge will save a ‘snaphot’ of the computers memory to disk that you can reload at a future time.
I also owned this one in the 80’s and still have it and the original box it came in.