The Anatomy of a Bottle: Comar’s Comprehensive Guide

This easy-to-understand bottle anatomy guide explores the different components of bottles, specifically packers for supplements, dropper squeeze bottles for controlled dispensing, and a range of designs for food and beverage.

From bases to neck closures, we’ll explain the key components and terminology, starting with a quick overview of the most essential factor: Bottle Materials.

Understanding Bottle Materials

When you’re choosing the right packaging solution, the material is pivotal for the product’s functionality and sustainability. For a deeper dive into PET vs. HDPE, please see our guide on choosing between these two highly popular options.

Below, we’ve included a quick overview of the most common materials used:

Each material has unique features that make it suitable for different packaging needs. Your choice of material can vary depending on what you’re packaging.

If you would like more support in determining the perfect material for your next project, reach out to Comar’s industry experts for support.

Understanding Bottle Terminology

Each component of a bottle serves a specific purpose. Understanding these terms can help you make the right choice when selecting a packaging solution. Here is a breakdown of the key parts of a bottle:

Mouth: The opening at the top of the bottle where the product is dispensed or poured out. The size and shape of the mouth determine the type of closure needed and the ease of product access.
Neck Finish: This refers to the configuration at the top of the bottle that accommodates the closure. It includes the neck’s size, threading, and style, which are important for ensuring a proper fit between the bottle and its cap.
- Threads: Threads are the spiraled ridges on the neck of the bottle that engage with the cap to close the container. The design of the threads (such as pitch and depth) is crucial for ensuring a secure fit and seal.
- Bead: The bead is a small ridge at the top of the neck, providing a catch point for the cap or closure. It plays a vital role in sealing the package and preventing leaks.

Shoulder: The shoulder of a bottle is where the body starts to curve or taper inwards towards the neck. It can impact the product’s flow when poured and contribute to the bottle’s overall strength.
Wall: This term refers to the sides of the bottle, extending from the shoulder down to the base. The thickness and material of the wall affect the bottle’s durability, barrier properties, and aesthetic appeal.
Label Panel: The flat area on the bottle’s wall is designed for label application. The size and shape of the label panel play a significant role in branding and information display.
Base: The bottom of the bottle, which can vary in design for stability, efficient use of space, or to match specific filling line requirements. Bases can also hold specific information like recycling symbols and registration marks.

Overflow: Overflow capacity denotes a bottle’s maximum volume when filled to the brim. This measurement varies from the intended capacity, which represents the measured volume the container is designed to hold.
Capacity: This is the volume a bottle is designed to hold during regular use, as opposed to its maximum (overflow) capacity. It is a key factor in product dosage and packaging efficiency.
Deco Lugs: Deco lugs are protrusions or indentations on the bottle, typically around the neck or shoulder, that determine the alignment of labels or decorative elements.

Understanding Bottle Measurements

When creating the ideal packaging solution, understanding key bottle measurements and terms is crucial for choosing the right option. Familiarity with these common measurements ensures you select the right option for your needs. Here are some of the most common measurements and terms you should know when choosing the right packaging solution.

Neck Finish Measurements

As previously discussed, the neck finish, or thread size, is the entirety of the protrusion from the container to which the closure (lid) is fastened. For clarification, wider-mouthed containers use “thread size” instead of “neck finish,” so you may see those terms used interchangeably.

Neck finishes are identified by two numbers separated by a hyphen, for example 38-400 as shown in the graphics. The first number (38 in this example) is always in millimeters (mm) and refers to the T dimension in Figure 1, it is the diameter of the outside threads.

As seen in the figure above, a 400 takes 1 full turn, 410 takes 1.5 turns, and 415 takes 2 full turns to close.

In conclusion, a 38-400 is a neck finish that is approximately 38mm wide (diameter) and takes 1 full turn to close.

Please Note: The neck finishes of the container and closure must match exactly to ensure an optimal fit and proper torque (twisting pressure) requirements for your bottle assembly.

cc vs. mL

For historical and practical reasons, plastic bottle measurements are sometimes expressed in cubic centimeters (cc) or milliliters (mL). While they might seem different, cc and mL are equivalent, representingthe same volume.

One cubic centimeter is equal to one milliliter.

The measurement cc is more commonly used in medical and scientific contexts, while mL is often used in consumer products.

The choice between cc and mL often depends on industry standards, regional preferences, and the product’s intended application. However, both measurements represent the volume of the container and can be used interchangeably.