Keeping saddle rails scratch free for possible return

[tulip]

Tape would likely leave sticky residue. How about paper under the tape?

[pll]

Plastic wrap, as in Saran wrap?

[Eden]

I'd try electrical tape. Shouldn't leave much residue and protects fairly well. I use it to wrap around my stays so that my clip on fenders don't scratch finish.

[Kiwi Stoker]

Just use orange degreaser to remove any sticky residue.

[ultraviolet]

When I was experimenting with various Specialized and Bontrager saddles, my LBS specifically said to use electrical tape on the rails to prevent scratches so there would be no issues with returns.