Why Round Wells? 96 Deep Well Plates, 1 mL to 2 mL
By Arctic White Team. Part of Meet The Plates, Ep. 3.
The short answer: pick round for the shape, then pick your volume
Our three 96 round-well deep well plates have round wells with round bottoms, on the standard SBS footprint. A round well has no corners, and these wells end in a round bottom instead of the Pyramid bottom on our square-well plate. That is the whole shape difference.
If your protocol calls for round wells, the choice left is volume: 1 mL, 1.6 mL working or 2.0 mL working per well. Check whether the number you are comparing is maximum, working or capped volume.
Watch it in 47 seconds
The three plates side by side
From the product pages, checked 2026-10-25:
| SKU | Volume per well | Well shape | Bottom | Case quantity |
|---|---|---|---|---|
| AWLS-219002 | 1 mL | Round | Round | 50 |
| AWLS-X10005 | 1.6 mL working | Round | Round | 50 |
| AWLS-X11005 | 2.0 mL working | Round | U-shaped round | 50 |
All three: 96 wells, polypropylene (PP), standard SBS footprint. AWLS-X11005 is rimless and has molded-in alphanumeric well labels. Browse all 96 well polypropylene plates.
Round vs square: what is different
No corners. A round well is one continuous wall, all the way around. A square well has four corners. In Ep. 1, why square wells, we worked through the square-well side: our 2 mL square-well plate, AWLS-S30009, has square wells and a Pyramid bottom.
A round bottom, not a Pyramid. All three round-well plates list a round bottom. The 2 mL plate, AWLS-X11005, describes its bottoms as U-shaped.
This guide covers shape, not performance. We are not claiming a round well does anything better than a square one. If your method or protocol specifies round wells or round bottoms, these are the three to compare.
The 2 mL round well, by the numbers
AWLS-X11005 is the one round-well plate whose product page lists its well and plate dimensions:
| Spec (AWLS-X11005) | Value |
|---|---|
| Well diameter, top | 8.53 mm |
| Well diameter, bottom | 7.20 mm |
| Well depth | 42.60 mm |
| Overall plate height | 45.30 mm |
| Rim | Rimless |
| Temperature rating | -80 °C to 120 °C |
| Maximum centrifugation | 4,000 RCF |
The well narrows by 8.53 - 7.20 = 1.33 mm in diameter from top to bottom, over 42.60 mm of depth. That puts 2.0 mL working per well in a plate 45.30 mm tall.
Then pick your volume
Two of the three product pages list more than one volume per well. Compare like with like.
| SKU | Maximum | Working | Capped or with mat lid | Case quantity |
|---|---|---|---|---|
| AWLS-219002 | 1 mL (one volume listed) | 50 | ||
| AWLS-X10005 | 1.7 mL | 1.6 mL | 1.5 mL capped | 50 |
| AWLS-X11005 | 2.1 mL | 2.0 mL | 1.9 mL with mat lid | 50 |
On both plates that list it, the capped or mat lid volume is 0.1 mL below the working volume (1.6 - 1.5 and 2.0 - 1.9). AWLS-219002 lists a single 1 mL figure without saying whether it is maximum or working, so treat it as nominal.
AWLS-X10005 is rated for storage down to -80 °C. AWLS-X11005 is rated -80 °C to 120 °C. The AWLS-219002 page does not list a temperature rating.
FAQ
Is a round well better than a square well?
This guide covers geometry, not performance. A round well has no corners and these plates have round bottoms; a square well has corners and our square-well plate has a Pyramid bottom. If your protocol calls for round wells, compare these three by volume.
Do all three plates have round bottoms?
Yes. All three product pages list round wells with a round bottom. The AWLS-X11005 page describes its bottoms as U-shaped.
What is the difference between maximum, working and capped volume?
They are three different numbers on the product pages. AWLS-X10005 lists 1.7 mL maximum, 1.6 mL working and 1.5 mL capped. AWLS-X11005 lists 2.1 mL maximum, 2.0 mL working and 1.9 mL with a mat lid. AWLS-219002 lists one figure, 1 mL. Compare the same kind of number across plates.
How tall is the 2 mL round-well plate?
The AWLS-X11005 product page lists an overall height of 45.30 mm and a well depth of 42.60 mm. The plate is rimless.
What temperature and centrifuge ratings do they have?
AWLS-X11005 is rated -80 °C to 120 °C, with a maximum centrifugation rating of 4,000 RCF. AWLS-X10005 is rated for storage down to -80 °C. The AWLS-219002 page does not list a temperature rating.
About Meet The Plates
Meet The Plates is a short series from Arctic White on lab plate geometry. Each episode takes one plate decision and works through it with the specifications on the product page. Ep. 1 covered why 96 deep well plates use square wells, and Ep. 2 covered which 96 well filter plate volume to pick.
Sources and math
Sources: the AWLS-219002, AWLS-X10005, AWLS-X11005 and AWLS-S30009 product pages on arcticsci.com, checked 2026-10-25. The math is our own working.
- Taper: 8.53 - 7.20 = 1.33 mm narrower in diameter at the bottom (AWLS-X11005).
- Capped vs working: 1.6 - 1.5 = 0.1 mL (AWLS-X10005); 2.0 - 1.9 = 0.1 mL (AWLS-X11005).
- No corners: a round well's opening is a circle, which has no corners. A square opening has four.