There are a couple Head Anion 135 rackets.
Image via amazon.com
The Anion2 is 135 grams, just like the the Xenon 135. But the Anion2 has strings going all the way down through the throat, whereas the Xenon has the crossbar. Here’s a picture of both rackets for comparison:
← Anion ← Xenon
According to the Head Website, the Anion2 is head-light and geared for power, whereas the Xenon is head-heavy and geared for control.
There’s also this Head Anion2 135 Ltd. I’m not really sure what is different about this racket besides the cosmetics, which are pretty cool.
Buy (UK): pdhsports.com