Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: Do the sides have a slight taper? I am looking for a slightly smaller dia. footprint than the 10.5 inche top.
Document: Safety is number one and this SIMAX is far away from toxic PTFE/PFOA, lead etc.. Actually those remarks already earn my 5 stars as health is valuable but Simax surpass my expectation not only sturdy (borosilicate glass and slightly thicker than Marinex I have for 10 years) but also good looking. Definitely 5 stars plus plus product and getting another plus as this one free shipping from AMAZON.
A few years ago I ordered an identical item from a different brand to use for bread dough to rise in the fridge, because the flat top allowed us to stack something else on top, and we are trying not to use plastic as much for food storage.
We were looking for a larger microwave safe glass casserole dish to cook rice in the microwave. Our old 2.5 quart dish would boil over and make a mess in the microwave. This 3.5 quart is perfect. It is wide and shallow, which concerned me for our intended use. We cook 1 cup of long grain white rice with 2 cups of water on high for 5 minutes, then on medium (50% power) for 8 1/2 minutes.
I used a 3 qt Pyrex for 35 years and the lid cracked. This was an excellent replacement. Its 3.5 Liters so a little bigger. The lid is deep and can accommodate a chicken or something higher than the bottom dish. The lid can also be used to bake as a shallow casserole. It cleans easily as long as you soak it in hot soapy water for a while, the surface is very smooth. This is well made and versatile.
I'm glad I ordered 3.5Q instead smaller one. This one fit in my tiny oven in our apartment. I have cooked baby ribs in it and turn out moist and tender. I can picture giant free range chicken in it too. I might have meatballs soup for the night with it, yumiii!! !This is definitely reminds me of my mom, the kitchen goddess. She only buys numero uno products which I didn't understand her as they cost a lot where I grew up.
Thank you AMAZON thank you SIMAX. Best Business Combo.PS: I hope Simax will bring visions cookware type and sell them through AMAZON. Can't wait ,,,
I've looked for years to find a quality replacement for my 40 year old Corning products which are finally wearing out. A lot of the new offerings available in today's market don't have the quality and/or the covers that I want. Simax does.
We use it almost every day and hope not to break it again.
Very pleased with this larger casserole dish. The size and shape is perfect for many of my recipes and it is easy to keep clean.
Great find! Works perfectly in the microwave. Looks fancy and washes up well. Many casseroles run over-not a problem with this size and accommodates the turntable.
Answer: Yes, the sides are slightly tapered.  The diameter at the base of the glassware that actually touches the table that it sits on is about 8 inches in diameter.  It is about 9.25 inches in diameter when measured from the tapered side at the bottom of the glassware before it curves into the flat sitting portion of the glassware.