Specifications

Solid Stopper · Specifications

Standard sizes are listed below. All products comply with GB/T, ASTM, and ISO standard taper systems. Full range 10/19 ~ 60/45 available. Custom materials and head types are available.

Request custom specs

1. Glass Solid Stopper (Standard Joint)

GB/T	ASTM	ISO	Joint Diameter (mm)	Construction	Head Type	Material
Please contact us to confirm the available specifications.

2. PTFE Solid Stopper

GB/T	ASTM	ISO	Top Diameter (mm)	Bottom Diameter (mm)	Overall Height (mm)	Material
Please contact us to confirm the available specifications.

3. Solid vs. Hollow Stopper Comparison

Feature	Solid Stopper	Hollow Stopper
Please contact us to confirm the available specifications.

* Joint numbers (10#, 14#) indicate the largest diameter (mm) of the taper. All are 1:10 taper.
* GB/ASTM/ISO designations are different standard identifiers — physical dimensions are identical and fully interchangeable.
* Full range 10/19 ~ 60/45 available upon request.
* Small sizes (10/30~19/38) are solid; larger sizes (24/40+) are typically hollow.
* PTFE withstands up to 260°C with low friction and non-stick properties.
* Contact our sales team for MOQ and lead time on custom orders.

✦ Customization Services — We offer custom joint sizes, materials, and head types. Share your specific requirements and our technical team will provide a tailored solution.

Product Description

The solid stopper is a fundamental accessory for sealing standard taper joints in standard taper glassware systems. Unlike hollow stoppers, solid stoppers feature a fully solid glass construction with a completely closed bottom, providing superior sealing performance. They are primarily used with volumetric flasks, separatory funnels, and iodine flasks that require high-integrity sealing.

Available in both glass and PTFE materials. Glass solid stoppers are manufactured from high-borosilicate glass 3.3 with excellent chemical and thermal stability. PTFE solid stoppers feature full PTFE construction with exceptional chemical resistance, compatible with virtually all chemical solvents.

Key Features

Borosilicate Glass 3.3 / PTFE: Glass type meets ISO 3585, thermal shock 280°C; PTFE type resists all chemical solvents
Multi‑Standard Compliance: Precision‑ground 1:10 taper meets GB/T, ASTM E, and ISO 3585 standard taper specifications for full interchangeability
Solid Construction: Completely closed bottom provides superior sealing performance
Multiple Head Types: Round (standard, most common), Octagonal (easy hand-tightening), Flat (space-saving)
High Transparency: Glass type allows clear viewing of contents
PTFE Type: Low friction coefficient, non-stick, resists strong acids/bases, withstands 260°C

Quality Assurance

Each solid stopper is inspected for taper accuracy and seal integrity to ensure reliable sealing with all standard joint components. Custom bulk orders are welcome.

Tip: Solid stoppers and hollow stoppers are not interchangeable. Volumetric flasks and separatory funnels must use solid stoppers for proper sealing. Ensure joints are clean and dry before insertion. Insert with a gentle twisting motion.

Applications

Typical Uses

Volumetric Flasks

Solid stoppers are required for accurate volumetric measurements

Separatory Funnels

Solid stoppers provide leak-proof sealing during extraction

Iodine Flasks

Prevent iodine vapor loss with solid stoppers

Reagent Bottles

Seal standard taper reagent bottles

High-Seal Applications

Any application requiring superior sealing performance

Compatible Equipment

Standard joint volumetric flasks

Separatory funnels, iodine flasks

Reagent bottles, standard joint flasks

Three-neck and four-neck flasks

Tip: Solid stoppers and hollow stoppers are not interchangeable. Volumetric flasks and separatory funnels must use solid stoppers. Always use matching standard joint sizes for optimal sealing.

Operation & Maintenance

User Guide

Before Use

Inspect for cracks, chips, or scratches on the joint
Clean the joint surface with a soft cloth to remove particulates
Confirm that the joint size matches your apparatus

Insertion

Align the stopper joint with the apparatus joint
Insert with a gentle twisting motion to ensure a tight fit
Octagonal heads can be tightened by hand using the octagonal grip
PTFE stoppers insert smoothly due to low friction
Avoid excessive force to prevent glass breakage

Removal

Remove with a gentle twisting motion
If stuck, use a heat gun to gently warm the outer joint
Clean joints immediately after removal

Cleaning & Storage

Clean immediately after use to prevent residue buildup
Use soft brushes and appropriate detergents for the joint
PTFE types can be cleaned with standard solvents
Air dry and store with protective paper between ground joints
Do not interchange stoppers between different volumetric flasks
Protect joints from impacts

Solid Stopper · Selection Guide

Four key dimensions determine the right solid stopper for your system: material type, head type, joint size, and application.

1. By Material Type

Material	Features	Typical Use
Please contact us to confirm the available specifications.

2. By Head Type

Head Type	Features	Typical Use
Please contact us to confirm the available specifications.

3. By Joint Size

Scale	GB/T	Typical Volume	Matching Apparatus
Please contact us to confirm the available specifications.

4. Quick Selection Checklist

Follow this decision flow to quickly identify the right configuration:

① Apparatus type? Volumetric flask / Separatory funnel → Solid stopper (required)
② Media type? Standard solutions → Glass | Acids/bases → PTFE
③ Frequent insertion/removal? No → Round | Yes → Octagonal
④ Scale? Micro → 10#/14# | Standard → 19#/24# | Large → 29#+

✦ Need help selecting? Contact our technical support team with your apparatus specifications and application requirements — we'll recommend the optimal configuration.

Care & Notes

Show care & notes

Safety Precautions

Observe temperature limits (PTFE: 260°C)
Wear protective gloves and safety goggles

Do not

Never use cracked or damaged stoppers
Do not interchange volumetric flask stoppers to maintain accuracy