Burette Clamp with Attached Boss Head

Quick Answer: The Burette Clamp with Attached Boss Head is a two-prong clamp whose rod is permanently joined to a boss head, so the unit fixes straight onto a retort stand upright. The listing image shows coated black jaws closed by a wing nut, and a boss head tightened by a blue knob.

One Unit Instead of Two

Most rod clamps arrive as a separate piece that needs a boss head before use. The burette clamp with attached boss head combines the two, so a class set cannot lose its connectors and nobody has to match boss heads to rods. The knob on the boss head tightens onto the stand upright; the wing nut on the clamp closes the prongs round the burette.

The trade-off is reach. With a loose boss head, the clamp rod can be slid in or out to set the distance from the stand; an attached connector fixes that distance. For a burette, which should hang close to the stand anyway, this is rarely a problem. For glassware that must sit further out, such as over a wide heating mantle, a separate rectangular boss head with an extension clamp gives more freedom.

In the pictured pattern the prongs also take test tubes, boiling tubes and thermometers. The title does not state the jaw range, so compare it with the widest item you intend to hold.

Specifications

Care & Handling

• Tighten the boss-head knob first, then close the prongs, so the burette is not twisted while the clamp is still loose on the stand.
• Close the wing nut until the glass is held but can still be turned by hand; overtightening cracks thin tubes.
• Keep the attached connector’s thread clean and dry, since it cannot be swapped like a loose boss head.

Applications

• Quick titration set-ups where students assemble their own stands
• Holding a thermometer in a beaker of water for heating and cooling curves
• Supporting a boiling tube during gas collection over water
• Holding a delivery tube or small funnel above a receiving vessel

Why Choose LabEquip

Schools that issue each student a stand and clamp at the start of a practical find attached-boss clamps quicker to hand out and collect. LabEquip includes this design in its General Lab Products range; for class sets, send numbers via the contact page.

Frequently Asked Questions

What is the advantage of an attached boss head?

The clamp and connector come as one unit, so it fixes to the stand in a single step and the boss head cannot be lost or mismatched. It suits class sets that are assembled and dismantled often.

Can the clamp be moved further from the stand?

Not much, because the rod length between the jaws and the boss head is fixed. If you need extra reach, use a separate boss head with an extension clamp instead.

Is it only for burettes?

No. A two-prong clamp of this kind also holds test tubes, boiling tubes, thermometers and the necks of small flasks. Match the jaw opening to the diameter of what you are holding.

How tight should the wing nut be?

Tighten until the item cannot slip down under its own weight but can still be rotated with a firm hand. Glass that is clamped rigidly and then heated can crack, because it cannot expand.

Can the direction of the clamp be changed?

Yes, the boss head can be turned on the stand upright to point the clamp another way before its knob is tightened. That lets one stand serve a flask on either side.

What should I check if the burette leans?

First check that the stand upright is vertical and the base sits on a level bench. Then check that both prongs close evenly; a bent prong pushes the burette to one side and should be straightened or replaced.

Last Updated: September 2026