They are only specific when it comes to whether they'll fit a Shimano/SRAM or Campagnolo chain. Shimano and SRAM use the same rear cassette spacing and thus the same chain widths (at least for 8 and 9 speed stuff, someone correct me on 10 speed stuff if I'm wrong) so you can use a SRAM link on a Shimano chain. Wipperman and KMC also make chains intended to be used with Shimano/SRAM compoments so those links will fit Shimano/SRAM chains as well. I think I've only seen Wipperman making Campagnolo chains with a removeable link but the same thing applies as with Shimano.