Round bottom, HEAVY WALL single short neck flask with a standard taper outer joint. The 29/26 flasks have a groove tooled just below the grind to aid in clamping of the flask. Please note: There are separate listings for different capacity single neck round bottom flasks.

SYNTHWARE round bottom, heavy wall, three neck flasks with standard taper outer joints on both the center neck and the angled side necks. All sizes are hand blown from tubing to ensure uniform wall thickness.

Round bottom Meets ASTM E1403, Type 1, Class 3

This borosilicate glass round bottom flasks has three necks - the center neck is vertical and the side necks are 180° apart and are inclined at an angle of 20° to the vertical. All necks have Standard Taper outer joints.

Round bottom Short ring neck These PYREX® round bottom boiling flasks have short ring necks. These ring neck boiling flasks are precisely tooled for uniform stopper fit. The reinforced rim increases mechanical strength. These flasks are used in applications requiring rigid stoppering…

Round bottom, HEAVY WALL single long neck flask with a standard taper outer joint.

With two vertical necks and a round bottom, these borosilicate glass flasks feature a side neck Standard Taper 24/40 outer joint. The center Standard Taper joint varies with flask capacity.

KIMAX® flasks have a low coefficient of expansion to resist thermal shock. They are constructed with sturdy walls to minimize mechanical breakage and reinforced tooled tops for strength and a secure stopper fit Designed from ASTM Specification E1403, Type I, Class I requirements …

SYNTHWARE round bottom, heavy wall, three neck flasks with standard taper outer joints on both the center neck and the vertical side necks. All sizes are hand blown from tubing to ensure uniform wall thickness.

Round bottom flask with short neck and outer joint. Available in standard and heavy wall. Heavy wall approximately 30% heavier than standard wall. Used by glassblowers in fabricating single or multi-necked flasks.

Manufactured from KIMAX™ borosilicate glass, ValueWare has a low coefficient of expansion and a very high resistance to chemical attack. This means optimal performance in the lab at an affordable price. Long life expectancy, resistant to most chemicals. Ideal for general laboratory use.…

Round bottom, single neck flask with septum port for use with air-sensitive material. Available in standard wall and heavy wall versions. All flasks supplied with a 9096-32 septum.

5 mL 14/20 center neck Single neck round bottom flask with an outer joint.

Single neck, flat bottom flask with a standard taper outer joint.

Boiling, round bottom flasks with ground glass joints. Our boiling flasks are made from low-expansion borosilicate glass. Feature uniform wall thickness for superior mechanical strength and shock resistance. Ideal for boiling, heating and mixing in the laboratory.

Borosil® Round Bottom Boiling Flasks have uniform wall thickness for even heat distribution. Constructed from stress-free borosilicate. Borosil® Boiling Flasks are heat-resistant. Built to withstand the demands of the modern lab, each flask has a flame-polished, Interchangable Joint, and an…

Borosil® Flat Bottom (Florence) Boiling Flasks have uniform wall thickness for even heat distribution. Constructed from stress-free borosilicate, Borosil® Boiling Flasks are heat-resistant. Built to withstand the demands of the modern lab, each flask has a flame-polished, beaded rim for…

Carefully designed and manufactured from borosilicate glass Wall thicknesses are carefully controlled to provide the proper balance between thermal expansion and mechanical strength for greater shock resistance Excellent chemical durability provides contamination-free results and long life…

These 250mL PYREX(r) low actinic flat bottom boiling flasks have full length outer 24/40 Standard Taper joints, but with shorter necks. Low actinic stained glass provides protection for materials sensitive to light. The protective color is an integral part of the flask, which retains the mechanical…

These PYREX(r) round bottom boiling flasks have full length outer Standard Taper joints, but with shorter necks. They are manufactured from No. 7740 borosilicate glass. Wall thicknesses are carefully controlled to provide the proper balance between thermal expansion and mechanical strength for…

Available in various sizes, these borosilicate glass round bottom flasks have three vertical necks with Standard Taper outer joints. The side necks are 180° apart.

SYNTHWARE round bottom, heavy wall, three neck flasks with a bottom outlet. Both the center neck and the vertical side necks are standard taper outer joints. The lower outlet is a 4mm straight bore PTFE stopcock. All sizes are hand blown from tubing to ensure uniform wall thickness.

Round bottom flask with four necks arranged 3 in-line and one at 90 degrees. 500ml and smaller flasks have angled side necks while larger sizes feature vertical necks. Available in heavy wall.

Available in various sizes, these borosilicate glass round bottom flasks have four vertical necks - one center neck and three side necks which are 90° apart. All necks have Standard Taper outer joints.

With outer joints with side necks angled. Available fabricated with heavy walls, approximately 30% heavier than regular wall flasks. Round bottom, three neck flask with angled sides. All joints are standard taper. Available in standard and heavy wall.<

KIMAX® round bottom boiling flask with a short neck and a medium length Standard Taper joint Designed from ASTM Specification E1403, Type II, Class III requirements Manufactured from 33 expansion, low extractable borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements

Two neck, one center and one angled side neck, round bottom flask with standard taper joints. Available in standard wall or heavy wall.

These 22L PYREX(r) round bottom boiling flasks have short ring necks and take a No. 14 rubber stopper. These ring neck boiling flasks are precisely tooled for uniform stopper fit. The reinforced rim increases mechanical strength. These flasks are used in applications requiring rigid stoppering and…

Round bottom flask with four necks arranged 3 in-line and one 10/30 joint at 90 degrees. The 500ml size has angled side necks while all other sizes feature vertical necks. Available in heavy wall.

These 1L PYREX® round bottom boiling flasks have long necks with tooled mouths and take a No. 8 rubber stopper. They are manufactured from No. 7740 borosilicate glass. Wall thicknesses are carefully controlled to provide the proper balance between thermal expansion and mechanical strength for…

SYNTHWARE pear shaped, heavy wall, two neck flasks with an angled side neck. All joints are standard taper outer joints. All sizes are hand blown from tubing to ensure uniform wall thickness.

Round bottom, single neck flask with Ace-Thred side port supplied with our 5029-10 nylon bushing and 7855-704 FETFE o-ring. Bushing is ideal for use with thermometers or bleed tubes of up to 7mm OD. Available in standard and heavy wall versions.