Burette Clamp, Extention, Double Keys 1

Quick Answer: The Burette Clamp, Extention, Double Keys 1 is a dual adjust extension clamp: each of its two jaws has its own thumbscrew, or key, so the grip can be set centrally or off-centre, and its long rod fits a boss head on a retort stand. The listing image shows a blue body with black-tipped prongs.

What the Two Keys Do

On a single-screw clamp both jaws move together, so the centre of the grip is fixed and a thin tube ends up wherever the jaws meet. With double keys, each jaw is driven by its own thumbscrew. One jaw can be set as a fixed stop and the other closed onto the glass, or both can be moved to place the item exactly where it must hang, for example directly over a narrow flask neck.

Independent jaws also help with objects that are not round or not straight: a tapered adapter, a thermometer pocket, or a thin probe held beside a thicker tube. The blue body in the photograph carries a screw on each side, with the long extension rod behind.

Compared with the Extention, Double Keys 2, this number has the longer rod and black-tipped prongs; the Double Keys 2 photograph shows a compact unit with orange plastic jaws. The title gives no rod length or jaw range.

Specifications

Applications

• Aligning a burette over a narrow-necked flask or a small beaker
• Holding a tapered item, such as a distillation adapter or funnel stem, without it tilting
• Clamping a thin probe or thermometer off-centre beside other apparatus
• Microscale set-ups in which small tubes must be placed to within a few millimetres

Care & Handling

• Loosen both keys fully before inserting glass, then close them alternately so the item is not pushed sideways.
• If the dual adjust extension clamp is kept for one set-up, mark which key sets the fixed jaw.
• Wipe the screw threads clean; a gritty thread makes fine adjustment difficult.

Why Choose LabEquip

Research groups and college labs that assemble distillation and microscale apparatus use dual adjust clamps where exact positioning matters more than speed. LabEquip lists this pattern in its General Lab Products range; enquire here with your rod and glassware sizes.

Frequently Asked Questions

What does double keys mean on a clamp?

It means the clamp has two adjusting screws, one for each jaw, so the jaws move independently. A single-key clamp closes both jaws together from one screw.

Why would I need independent jaws?

They let you decide where the held item sits relative to the rod, and they hold tapered or uneven items without forcing them off-line. That helps when glass must line up with a joint or a flask neck below.

How do I clamp a burette centrally with two keys?

Open both jaws, place the burette, then turn each key a little at a time until both jaws touch the glass. Check from above that the burette sits where you want it before the final tightening.

Is a dual adjust clamp slower to use?

Slightly, because there are two screws to turn. For class titrations where speed matters, a single-screw or spring clamp is quicker; the double keys pattern pays off when positioning matters.

Can the prongs damage glass?

Not if the black tips are intact and the keys are not overtightened. Glass should be held firmly enough not to slip but never squeezed hard, especially if it will be heated.

Does it need a boss head?

Yes. The extension rod is held in a boss head on the retort stand, which also lets you set how far the clamp reaches out.

Last Updated: September 2026