GL45 Blue Cap Media Bottles

The GL45 media bottle is the standard storage bottle of the modern laboratory. GL45 refers to the 45 mm GL thread on the neck, a widely adopted format that accepts caps, pouring rings and connector caps from many labware ranges. We supply it in borosilicate 3.3 glass, which handles heat, thermal shock and most chemicals well.

Each bottle comes with a blue polypropylene screw cap and a separate pouring ring for drip-free dispensing, and the whole assembly is built for repeated washing and autoclaving in routine lab use.

Labs use GL45 bottles to prepare and store cell-culture media, buffers, reagents and solvents, to hold samples, and to sterilize liquids in the autoclave. They are everyday equipment in bioprocess, QC, pharmaceutical, food-testing and general chemistry labs, and in teaching labs. Because the GL45 thread is so widely used, the same bottle can take ported caps and tubing connectors for media transfer and bioreactor feeds, so one bottle format covers storage, sterilization and transfer.

The bottle is formed in borosilicate 3.3 with a GL45 thread and a clean pouring lip. A fired enamel volume scale and a white marking spot sit on the body; the scale is approximate and meant for guidance, not accurate measurement. The cap and pouring ring are autoclavable polypropylene, and cap seals are available in PP or PTFE-faced silicone where better chemical resistance is needed. Capacities run from 100 ml bench bottles up to 20 L.

Fit the pouring ring under the cap for clean dispensing. When autoclaving, leave the cap loosened by about a turn so pressure can equalize; a tightly closed bottle can crack or implode as it cools. Let bottles cool before handling and avoid sudden temperature swings on hot glass. For volatile solvents or aggressive chemicals, ask us for a PTFE-faced cap seal so the closure suits the contents.

Our GL45 bottles are formed from low-expansion borosilicate 3.3, annealed, and finished to the GL45 thread profile so caps interchange. Graduations and marking spots are screen-printed in enamel and fired on. We can supply amber glass, other cap colors for color-coding, custom printed logos or scales, and cap-and-ring sets packed separately. Send us your sizes and quantities and we’ll quote and arrange samples for sign-off.