OK, another pair of unknown extender cards: http://ana-3.lcs.mit.edu/~jnc/tech/jpg/tmp/LargeExtender.jpg
If anyone has a use for one or both, FTGH. They are 17"x10", and the support arms (nice touch) are about 3" long. No identifying marks that I can perceive, alas. The power leads are titled "+5", "+12 Handler", +12 Return", "+12 Scan", "+15", "+- 15 Return", "-15". Noel