aka "Soft Ties."
Is this for securing luggage / stuff sacks, or tying down the bike for transport?
I always use soft ties, "always" meaning on the rare occasions my bike is shackled in disgrace to a trailer.
NOTE: I live in the South, so for those who deal regularly with snows and ices, no disrespect. But there's seldom an excuse to put a bike on a trailer, down here. If it is, that means I dug myself a mechanical sinkhole, and am seeking aid as I retreat.
EDIT: another new fave of mine (well, not really so "new") are RokStraps, in lieu of the notorious and formerly ubiquitous bungee cords:
https://rokstraps.com/
Found at all the usual online retailers, and sometimes locally. Depending on what is "local." Especially useful if you have an empty tail rack, like with no top box on it.