Factual error: Walter gives the volume of additional air/oxygen from the tank as "298 cubic liters", it is either cubic ft, cubic meters or simply liters, not cubic liters. (00:32:35)
Continuity mistake: The tail number of the plane Walter is in changes. (00:30:00 - 00:31:00)
Single Point of Failure - S1-E2
Character mistake: In the letter informing him of his sister's condition it says "Nor have I scene" instead of "seen". I would not expect a medical professional to make that sort of error. (00:02:20)
Other mistake: When Happy goes to see if the backhoe will work to finish freezing the water she says the hoses are damaged. The hoses she indicates as damaged are the ac lines and hydraulic lines that hydraulic oil flows through - she does not even look at the water hoses. (00:18:40)
Answer: They are a real device. You can find more information online. Just google "stun-cuff."
raywest