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USA Lab
Spherical Joint Round Bottom Receiving Flask - 1 neck 35/20
$20.00 - $55.00
In stockPrice varies by Size.
Single-neck round bottom receiving flask with a 35/20 spherical (ball) joint, listed in 250 mL, 500 mL, 1 L and 2 L. Spherical joints clamp rather than taper, so the flask can sit at an angle to the take-off. Glass grade is not documented and no ball-joint clamp is listed as included.
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Description
Single-neck round bottom receiving flask with a 35/20 spherical (ball) joint, listed in four capacities.
- 250 mL (RBF250SPH)
- 500 mL (RBF500MLS35)
- 1000 mL / 1 L (RBF1LS35)
- 2000 mL / 2 L (RBF2LS35)
- Joint: 35/20 spherical, one neck
A spherical joint is clamped rather than tapered into place, so the flask can be angled relative to the mating fitting. That is why this style is specified on receiving positions where the flask does not sit square to the take-off. In standard spherical joint designation the first number is the ball diameter in millimetres and the second the bore, so a 35/20 flask mates only to another 35/20 fitting.
Glass grade, wall thickness and overall dimensions are not documented on this listing, and a matching 35/20 ball joint clamp is not listed as included.
Frequently asked questions
What sizes are available?+
Four: 250 mL (RBF250SPH), 500 mL (RBF500MLS35), 1 L (RBF1LS35) and 2 L (RBF2LS35).
What does 35/20 mean?+
It is the spherical joint designation. In the standard convention the first figure is the ball diameter in millimetres and the second is the bore, so mating components must also be 35/20.
Is a clamp included?+
Not documented, so assume not. A 35/20 ball joint clamp, and a gasket if your setup uses one, would be ordered separately.
What glass is it made from?+
Not documented on this listing. No borosilicate grade is stated. Ask us before ordering if you need a specified glass grade.
Will it fit my short path or rotary evaporator take-off?+
Only if that equipment terminates in a 35/20 spherical joint. Check the joint designation stamped or specified on your take-off before ordering; a taper joint such as 24/40 will not mate to it.
Are wall thickness or overall dimensions published?+
No. Neither is documented on this listing.
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