The CRKT Companion is a tactical knife, I believe. If you need a neck knife as a backup to a tactical knife, I don't think the arclite would qualify. It does not have a secure handle for stabbing.
While it costs much more than $20 and can be quite hard to find, possibly the best factory tactical neck knife is the Emerson LaGriffe. Low priced alternatives are the CRKT Bear Claw and the S&W Badge Knife. I think you can get the Badge Knife for under $20 - not sure about the Bear Claw.
The Emerson LaGriffe ranges from $50 to $70 at online shops, but chances are you won't find one at the shops with the lower prices. I have one on the way from 1SKS. Their price is $65.
While it costs much more than $20 and can be quite hard to find, possibly the best factory tactical neck knife is the Emerson LaGriffe. Low priced alternatives are the CRKT Bear Claw and the S&W Badge Knife. I think you can get the Badge Knife for under $20 - not sure about the Bear Claw.
The Emerson LaGriffe ranges from $50 to $70 at online shops, but chances are you won't find one at the shops with the lower prices. I have one on the way from 1SKS. Their price is $65.