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UNITED SCIENTIFIC SUPPLIES Stopper: Rubber, 3 Stopper Size, 18 mm Bottom Dia, 24 mm Top Dia, 25 mm Overall Ht - Rubber Stoppers

UNITED SCIENTIFIC SUPPLIES Stopper: Rubber, 3 Stopper Size, 18 mm Bottom Dia, 24 mm Top Dia, 25 mm Overall Ht

The UNITED SCIENTIFIC SUPPLIES Stopper: Rubber is a black rubber stopper in size 3, featuring a bottom diameter of 18 mm, top diameter of 24 mm, and overall height of 25 mm. This stopper includes 2 holes and is…

SKU 3G-OTH-381362

Also listed as: RST3H2 · RST3 H2

Brand
UNITED SCIENTIFIC SUPPLIES
Item
Stopper: Rubber, 3 Stopper Size, 18 mm Bottom Dia, 24 mm Top Dia, 25 mm Overall Ht
Category
Rubber Stoppers
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

UNITED SCIENTIFIC SUPPLIES
Manufacturer Part Number
RST3-H2
Type
Black
Material
Rubber
Color
Black
Holes
2
Top Dia
24 mm
Bottom Dia
18 mm
Overall Ht
25 mm
Stopper Size
3

Technical Documents

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UNITED SCIENTIFIC SUPPLIES Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The UNITED SCIENTIFIC SUPPLIES Stopper: Rubber is a black rubber stopper in size 3, featuring a bottom diameter of 18 mm, top diameter of 24 mm, and overall height of 25 mm. This stopper includes 2 holes and is manufactured by UNITED SCIENTIFIC SUPPLIES INC under part number RST3-H2.

Frequently Asked Questions

What is a UNITED SCIENTIFIC SUPPLIES rubber stopper size 3 with 2 holes used for?

This black rubber stopper (size 3, 18 mm bottom dia, 24 mm top dia, 25 mm height) seals laboratory flasks, test tubes, or bottles. The 2 holes allow insertion of glass tubing, thermometers, or probes for gas transfer or vacuum applications in chemistry and biology labs.

What are the specifications of the UNITED SCIENTIFIC SUPPLIES RST3-H2 rubber stopper?

The RST3-H2 is a black rubber stopper, size 3, with a bottom diameter of 18 mm, top diameter of 24 mm, and overall height of 25 mm. It has 2 holes and is made by UNITED SCIENTIFIC SUPPLIES INC. The material is rubber, suitable for general-purpose laboratory sealing.

Where to buy UNITED SCIENTIFIC SUPPLIES rubber stoppers worldwide?

3G Electric supplies the UNITED SCIENTIFIC SUPPLIES RST3-H2 rubber stopper to customers worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for a quote and lead time on this lab consumable.

How to select the right rubber stopper size for a flask?

Measure the inside diameter of your flask neck. The stopper's top diameter (24 mm for size 3) should be slightly larger than the neck opening, while the bottom diameter (18 mm) fits inside. Ensure the stopper compresses to form a tight seal. For 2-hole needs, choose a pre-drilled stopper like the RST3-H2.

UNITED SCIENTIFIC SUPPLIES Products

3G Electric supplies UNITED SCIENTIFIC SUPPLIES rubber stoppers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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