Comment # 12 on bug 1217919 from Franck Bui

(In reply to Robert von Knobloch from comment #11)
> lrwxrwxrwx 1 root root 6 Dec 30 09:36 8:48 -> ../sdd
> lrwxrwxrwx 1 root root 7 Dec 30 09:36 8:49 -> ../sdd1

Here it shows that your rule matches both the block device itself as well as
the partition one, which is quite expected since both share the same product
name.

You should fix it.

> p.s. I tried adding the serial number as a condition, but had no luck.

Same remark as above, the serial number is an HW property shared by both
devices.

I forgot to ask the output of:

 # ls -l /dev/char/ | egrep "189:131|21:4|246:4"

One of them most likely points to "bus/usb/002/004" but I'd like to be sure.

Thanks.