There seem to be at least two types. Here are some photos showing an example of each:
Kurt Sperry Bellingham, Washington USA
2009/11/24 Mark Battley <mark.battley@xtra.co.nz>:
> Hi again,
>
> Does anyone have a picture of what a Legnano seat binder bolt should look
> like?
>
> This is for an early/mid 60s frame (?) with the bolt in front of the seat
> tube, without a split in the seat-tube
>
> http://picasaweb.google.com/
>
> At present it has a bodged version made of two hand filed aluminium wedges
> with an ugly bolt that clamps them together against the post. It seem like a
> reasonable solution, if poorly executed, but I'd like to see what a real one
> should be.
>
> Thanks,
>
> Mark Battley
> Auckland, New Zealand