Plastic stick bite trays

[JSnyder85]

Has anyone come across these plastic bite trays that have the horizontal and vertical bar? Does anyone know who makes them?

 

[JSnyder85]

Also, is anybody familiar with Kerr impression compound? I was wondering the procedure for impressing and also pouring up this material. I know its a very old school technique and i only see it once in a blue moon but i always have issues when pouring it up, especially when used with copper band tubes.

 

[griffmar79]

Esthetic CrossRef

 

[JSnyder85]

Thank you