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USA Lab
2-Neck Round Bottom Flask – Borosilicate 3.3 Glass
$20.00 - $249.00
In stockPrice varies by Size.
Two-neck round bottom flask in 3.3 borosilicate glass, listed in nine size and joint combinations from 250 mL to 10 L. Smaller sizes are listed at 24/40; the 2 L, 5 L and 10 L options pair a 34/45 or 45/50 centre joint with a 24/40 side joint.
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Description
Two-neck round bottom flask in 3.3 borosilicate glass, listed in nine size and joint combinations from 250 mL to 10 L. Each combination is a separate SKU, selected on this page.
Options given with a single joint size:
- 250 mL — 24/40 (250RBF2NECK)
- 500 mL — 24/40 (RBF500ML2NECK)
- 1 L — 24/40 (RBF1L2Neck)
- 2 L — 24/40 (RBF2L2Neck)
- 5 L — 24/40 (RBF5L-2NECK-2440)
Options with a larger centre joint and a 24/40 side joint:
- 2 L — 34/45 centre, 24/40 side (2LRBF-3445-2440-2N)
- 5 L — 34/45 centre, 24/40 side (RBF5L2NECK-2434)
- 5 L — 45/50 centre, 24/40 side (5LRBF-4550-2440-2N)
- 10 L — 45/50 centre, 24/40 side (10LRBF-4550-2440-2N)
Wall thickness, overall height and flask outside diameter are not documented on this listing, and no mantle, support or stopper is listed as included. Check the outside diameter against your heating mantle before ordering.
Frequently asked questions
Which size and joint combinations are available?+
Nine. Listed with a single joint size: 250 mL, 500 mL, 1 L, 2 L and 5 L at 24/40. Listed with a larger centre joint plus a 24/40 side joint: 2 L with 34/45 centre, 5 L with 34/45 centre, 5 L with 45/50 centre, and 10 L with 45/50 centre.
What glass grade is used?+
Borosilicate 3.3, as stated on the listing.
On the options listed with only one joint size, what size is the second neck?+
The listing does not distinguish the two necks on those options. Confirm with us before ordering if the side neck size matters to your setup.
Are stoppers, clips or adapters supplied?+
No. This listing covers the flask only.
Is wall thickness or overall dimension documented?+
No. Wall thickness, overall height and flask outside diameter are not stated on this listing.
Can these be used on a heating mantle?+
A round bottom flask is normally supported in a matched hemispherical mantle or cradle, but no mantle size and no maximum operating temperature is documented here. Confirm the flask outside diameter against your mantle before ordering; no mantle is included.
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