I made a glass dewar for a customer who says it doesnt work for lack of vacuum coductivity. what does it mean?

Question

the dewar was oval shaped and i put pegs inside it to hold it in place. it got rejected because they said those pegs broke up the vacuum conductivity? what does this mean?

Answer 1

It means they are saying the pegs conduct some heat from the inside skin to the outer one or vice versa.