Just because a Mezuzah, pair of Tefillin, or a Sefer Torah look kosher, it doesn’t mean that they are kosher. Unfortunately, since usually there is no one overseeing the intricate process of producing STA”M, there are passul Tefillin and Mezuzos even in reputable Judacia stores across the United States and elsewhere. This may be due to a mistake made by a Sofer who isn’t well versed in the relevant Halachos, or perhaps even by unqualified Sofrim who don't care about the Kashrus of their product. And "Checking your Mezuzos" can in no way verify wether they are Kosher, since there are many things that render STa"M passul that cannot be seen on the finished product. Check out the full article from Hamodia Magazine.

Zichron Olam is therefore proud to offer you Star-K certified STa"M, so that you can rest assured that the STa"M that you purchase was overseen by somebody you trust.

The Star-K first verifies that every Sofer has a Ksav Kaballah, and samples his Ksav to insure and that it is up to par. Aside from all this, every Sofer is individually investigated to insure that he is a Yarei Shamayim.

Each and every Magiah is also investigated to insure that he knows the Halachos and can be trusted. Every piece of STa"M must be checked both manually and via a sophisticated computer program to insure that there are no mistakes.

In regard to Tefillin, only Star-K approved Batim and Retzuos are used. Even the person who inserts the parshiyos must be approved before he may participate in any part of the process.

Finally the Mezuzos and Tefillin are sealed and packaged and a Star-K symbol is stamped on the outside, so the consumer can be assured that his STa”M meets the highest Halachic standards.

Since Sifrei Torah are completed at the time of the Hachnasas Sefer Torah, the Star-K is unable to seal and stamp the finished product. Therefore every sefer Torah is scanned and archived so the purchaser knows that the Sefer Torah he is holding has been certified by the Star-K. Since Sifrei Torah are handwritten, no two are ever exactly alike. The minute differences apparent to the trained eye, act much the same way as fingerprints to provide each Sefer Torah with its own distinct identity. The digital archives can then be accessed in order verify that the Sefer Torah purchased was indeed certified by the Star-K.

NOTE: Although all of the STa"M are thoroughly examined for errors, people are only human and computers are only machines, therefore there is always a slight chance that there will be mistakes.