• Aluminum die-cast make reliability is high. It is the speaker clamp.

• Parts Express clamp kit P.N. 262-869

Originals?
they look like the JBL type I was looking for and I am asking for prices.
http://www.kozystudio.com/audio/rasystem/clamp.htm

the translation here: http://66.249.93.104/translate_c?hl=en&langpair=ja%7Cen&u=http://www.kozystudio.com/audio/html/main.htm

(It's the problem we have when the webmaster is not a good one.
We have to look for the right webaddress because of html "frames".)

Also in plastic: ADAM HALL 5909
http://www.thomann.de/fi/adam_hall_5909_lautsprecherklammer.htm
http://www.adamhall.com/uk/index.php?cccpage=x3shop_2&set_katnav=30&set_prefpage=1

Similar model: Speaker Clamp, Cast Zinc, Black
http://www.reliablehardware.com/shoppingcart/item/243

• Speaker Clamp