The external strip of this pendant is a known geometrical shape called "the Mobius strip". The Mobius strip has no sides and it represents the fact that all that exists is made out of the one which created it all from himself. In fact, all that we experience as external to us is just a different manifestation of the same one in a different level of consciousness (for more details please read the "Mobius strip" article).
In the middle of the pendant, there is the Hebrew word – VESHIVITI which is a part of the sentence – VESHIVITI ADONY LENGDY TAMID. The sentence's translation is – “And I put g-d in front of me always”. The meaning of this sentence is that g-d is in everything and that he “wears” all different life forms. The understanding of this idea can help us transcend to a higher state of consciousness. The use of the VESHIVITI motive is widely spread in Jewish artworks throughout the generations.
The two circles crossing each other are a known shape called "the Vesica Pisces", representing the basis for the physical structure of light.
The pendant is made to help the wearer realize that g-d is in all and that we are all interconnected.