$20 for a HP 28, I have two of these
and
$15 for a HP 27, I have two of these as well
For more details, see
http://h10010.www1.hp.com/wwpc/us/en/sm/WF06c/A10-12771-64199-69422-69422-81852-79807-79812.html
and
http://www.shopping.hp.com/product/C8727AN?landing=supplies&category=ink_toner&family_name=
Please do not message this poster about other commercial services.
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