Aspirator Bottles, Screw Cap with Socket Outlet

Quick Answer: The Aspirator Bottles, Screw Cap with Socket Outlet are reservoir bottles with a screw cap on top and a ground-glass socket at the bottom outlet. An aspirator bottle with socket outlet accepts a stopcock with a matching ground cone, so liquid is dispensed straight from a tap on the bottle.

What a Socket Outlet Adds

A socket outlet is a ground-glass female joint formed at the base of the bottle. It is made to accept a stopcock, or tap, whose outlet ends in a matching male cone. Because the ground surfaces fit closely, the tap seals without rubber bungs or tubing, and it can be removed for cleaning or replaced if it breaks. Joint sizes are standardised, so the size of the socket must match the cone on the tap.

This design gives cleaner, more controlled dispensing than a tubulation with tubing. There is no rubber to perish or taint the contents, the liquid meets only glass and the tap key, and a turn of the key starts or stops the flow directly over a beaker or flask. The screw cap on top keeps the reservoir closed between uses; loosen it or use a vented cap when dispensing so air can replace the liquid.

The listing does not say whether a stopcock is supplied, what joint size is used, or the capacity and glass type. The aspirator bottle with tubulation is the simpler alternative when tubing is preferred.

Specifications

Looking After the Ground Joint

• Apply a thin film of suitable grease to a glass stopcock cone, or use a PTFE key that needs none, so the joint neither leaks nor seizes.
• Secure the stopcock with a joint clip if it tends to work loose.
• Remove the tap before washing the aspirator bottle with socket outlet, and never leave alkaline solutions standing in a ground joint, as they can make it stick.
• Store the bottle with the tap removed or loosened, with a strip of paper in the joint.

Applications

• Bench reservoirs of distilled water dispensed directly by tap into beakers and flasks
• Stock solutions for titration benches and staining stations where rubber contact is undesirable
• Reagent supply in teaching labs where students dispense their own aliquots
• Water supply for rinsing electrodes and glassware

Why Choose LabEquip

Laboratories that dispense water or reagents many times a day prefer a tap fitted directly to the bottle, and a ground socket makes that tap replaceable. LabEquip lists these bottles in Biology Lab Products; send the joint size and capacity you need through the contact page.

Frequently Asked Questions

What is a socket outlet on an aspirator bottle?

It is a ground-glass female joint at the bottom outlet. A stopcock with a matching ground male cone fits into it, forming a seal without rubber bungs or tubing.

How is a socket outlet better than a tubulation?

A ground socket gives a leak-tight, removable glass connection and avoids rubber tubing that can perish or contaminate the contents. A tubulation is cheaper and more flexible where liquid must be led away through tubing.

Does the stopcock need grease?

A glass key usually needs a thin film of stopcock grease to seal and turn smoothly. PTFE keys are normally used without grease.

Why has the stopcock seized in the socket?

Alkaline solutions and dried residues can bond ground glass surfaces together. Soak the joint in warm water, tap it gently with a piece of wood, and in future remove or loosen the tap before storage.

Can a different tap be fitted?

Yes, if its cone matches the socket size. Ground joints are made in standard sizes, so check the size marked on the socket before buying a replacement.

Is a stopcock supplied with the bottle?

Some bottles are sold with a matching stopcock and others as the bottle only. The listing does not say which applies, so confirm it when you enquire.

Last Updated: September 2026