Anyone know what sort of link this is?

[k0ua]

Easy-to-use galvanized malleable iron connectors lock together and stay closed under tension. Ideal for cable stringing and pulling. Warning: Not for overhead lifting. Not for use as a link for chain or to repair chain.

From the McMaster Carr listing.

 

[Capricious]

From the McMaster Carr listing.

The ones I have do not impress me as being all that sturdy, so I have never used them for anything.

 

[chim]

ALLRIGHT!! I knew the brain trust wouldn't let me down. Now with the info from Capricious and Xfaxman they've been tracked down. Thank you!