Zalkin Capping Solutions for Tethered Caps / Closures


Tethered caps


In 2019 the EU voted the Single Use Plastics (SUP) Directive on how to deal with single-use plastic products. Under this Directive, in the future, drinks will only be allowed to be sold in plastic containers if the tethered cap / tethered closure remains attached to the container.

Early 2021 National laws transposed from the Directive has come into force. This has made tethered closures an omnipresent topic in the packaging industry.

Zalkin had already started to work with its partners and customers and can adapt the existing capping machines to be ready by 2024.

Zalkin Custom Development

Zalkin know-how allows to develop innovative capping applications, including lightweight and tethered.

The Directive on tethered closures highlights how crucial it is that designs combine circular economy and consumer-friendly closures. This is why Zalkin has worked hard with cap and packaging manufacturers to find solutions for caps that not only meet the sustainability requirements but also improve consumers’ experiences.

Zalkin has a long experience in helping develop new caps and building turrets and cap-sorters for tethered caps.


With its ZC Lab test laboratory Zalkin has advised and assisted for developments on


  • Caps

Tethered caps have to offer customers the same physical performance as standard closures.

To achieve this requirement the cap and the way it is applied to the bottle has to be updated, and sometimes even redesigned.

  • Neck finishes

Closures ideally need to be implementable without the need for modifications to the neck finish and without any loss of efficiency in the handling processes.

  • Capping process

Various solutions have been developed that can be adapted to all important bottle neck sizes

  1. with minimum conversion effort
  2. without negatively affecting the application processes

Zalkin has a large experience in tethered capped bottles for water

In close cooperation with our customers we have pioneered since 2015 the tethered snap cap in the water industry. This has been a great challenge and success as today millions of water bottles are tethered-capped with our machines all over the world.

Our cappers are capable of reaching high speed when capping either still or sparkling water.

This long experience in building or converting machines for tethereds cap places Zalkin in the best position to help our customers in all the phases of this major change.

We can help you in

  • developing and testing your sustainable and user-friendly caps
  • finding the best option for the evolution of your capping lines
  • optimizing the capping process from the bulk to the quality control


Zalkin will at your side to be ready by 2024 !!

EU Single Use Plastics (SUP) directive

The SUP directive in a nutshell


Objective of this new directive

  • Reduction for marine littering, as plastic closures from PET bottles have been identified as a major cause for pollution and high risk for marine wild life (ingestion).


Proposed solution

  • To reduce/eliminate closures from separate littering by attaching closures to the bottle till the end of life of the bottle.


In the EU definition, all closures for PET bottles for beverages should be converted to tethered by 2024.

Impact on environment & packaging collection rates

Reducing the impact of single use plastic on the environment

Beverage PET bottles will have to contain

  • From 2025 - at least 25% recycled plastic
  • From 2030 - at least 30% recycled plastic


Necessary measures to collect separately an increased amount of waste single-use plastic products for recycling:

  • No later than by 2025, amount equal to 77% (plastic products placed on the market in a given year by weight)
  • No later than by 2029, an amount equal to 90%

Impact on other liquid & dairy products

Tethered caps are not only snapped for water

Next to this first solution, cap manufacturers and packaging companies have developed tethered screw caps for PET bottles and worked on solutions for HDPE bottles/containers.

The snap clic closure originally for water PET bottle has already been adapted for dairy products and meets the SUP directive.