Aside from the lace used for the cup the Tango II Balconette (3251) and the Tango II Two Tone Balconette (5061) are exactly the same bra.
The Tango II Two Tone was a variant of the normal Tango II that was brought out every once in a while. Like a seasonal colour, with the difference that they used slighty different lace too. The last Tango II Two Tone I am aware of was the teal/mint variety from AW 2009. Other older variants are black/white and pink/ivory.
The embroidery of the Two Tone is almost flat and a lot less lumpy than the embroidery on the regular Tango, thus it is less visible under thin t-shirts
I added a picture that compares the lace of the normal Tango II with the lace of the Tango II Two Tone.
This bra almost fits me. I think if the cups were a bit wider and/or a slightly different shape so that the wires didn't dig into me under my arms, and the straps were set at a slightly different angle, it might fit very well indeed. This is what passed for fitting until I found something slightly better.
The embroidery does show through clothing some. As with all my Panache bras, the underwires are stiff and heavy, and the bit of band beneath the cups rolls up.