what tubs are flat on bottom with no indents ????

I am building new rack for females was looking at 41q sterlite I think or rubber maid cant remember all I know is that they were a bit slimmer and longer but they got the indent . iris have indent or not?

others that had these same thought please chime in and let me know what way u went ..

the indent don't really bother me I still get the heat right but it just annoys me that the tubs have indents .. im just anal about somethings

thanks for reading and whatever advice u can give

peace.. steve