We have been working side by side with customers for nearly 25 years fabricating custom glassware to suit their needs. Whether it is a completely custom item or a custom modification to an existing catalog item we are happy to accommodate you. Just provide us with a blueprint or even a simple hand drawing will do and we are happy to help.

Four and Five Neck Round Bottom Flasks for Complex Reactions

When a reaction calls for more simultaneous connections than a standard flask can offer, our four-neck round-bottom flasks give you room for a condenser, thermometer, addition funnel, and inert gas line all at once. We fabricate these flasks in a range of capacities and joint sizes, and because each one is hand-blown in-house, five-neck configurations and other specialized layouts are just as easy to produce. These flasks are especially useful in pharmaceutical synthesis, process chemistry, and academic research where multiple simultaneous operations are common.

Custom Configurations Built to Your Specifications

If a catalog listing does not match your project exactly, send us a blueprint or a simple hand drawing, and we will build a four-neck round-bottom flask to your specific joint placement and capacity. We keep commonly used sizes in stock for fast nationwide shipping, and our repair team can restore a damaged flask to near-new condition when possible. Backed by nearly 25 years of scientific glassblowing experience, we work directly with chemists and lab managers to get complex reaction glassware right the first time. We’re happy to talk through your setup before you order.

These configurations are common in scale-up chemistry, where a process that once ran in a single neck flask needs additional ports for a mechanical stirrer, dropping funnel, nitrogen line, and temperature probe all running at the same time. We size the necks and joints to match your existing equipment so you’re not left buying new adapters or stirrer shafts just to accommodate a new flask. For labs standardizing across multiple fume hoods, we can also produce a matched set so every station uses identical glassware.