K-visa was for fiance or fiancee to come to the United States to marry the US citizen fiancé or fiancée, due to justified reasons that the US citizen can not go overseas to marry in the alien's home country. This special visa category was designed for unmarried couples only but was modified a few years ago to include married couples as well, primarily for "equal protection" rights due to procedural delays caused in the USCIS processing pipeline.
So, now we have K-1 for fiancé or fiancée and K-3 for married spouse. K-1 dependents are K-4s and dependents of K-3 are issued K-4 visas.
Please provide us with as much information as possible regarding your case or questions and, if you have a pending case with a receipt number please also provide it. If you have a challenge from the USCIS either in form of a "Request for Evidence" (RFE) or "Intent to Deny" (ITD) or "Intent to Revoke" (ITR), please provide us either a copy of that challenge through email or fax (972-994-0088) so that we have a better understanding of the problems at issue.
If you case was recently denied at a US Consulate overseas, please provide the denial notice if you have one so that we can try to locate the records based on the case reference numbers contained in the denial.