Interdimensional extrapolator

Cisco Ramon created an inter-dimensional extrapolator that allows Kara Danvers to travel from her Earth to Earth One any time she wishes, as well as communicating with him.

History
Wishing to give Kara Danvers the ability to travel between Earths herself, Cisco Ramon created an inter-dimensional extrapolator. He gave it to her as a gift, also explaining that it had communication functionalities. She later used it, opening a small breach from Earth One to Earth Thirty-Eight, travelling between them.