0 so connectivity is very good. These marks did not come off. If you have even a corner lamp on near you, it goes away. Happy customer. I took a chance and ordered the Calinda flat and one other style, both in size 8 1/2 M. As good as always ‘Slight delay. They fit perfectly (I bought the wide width) and have an incredibly cushioned heel. I was really excited to organize my pantry and see all my spices by using these. The value from the low affordable price tag and ease of mod-ability is where the F300 shines!