Sling Design

Built from the Best Materials, Refined by Design

Greenline Sling is engineered using only UHMWPE and ultra-lightweight titanium alloy.
All textile components of the sling body—including the pouch, retention cord, and release cord—are made from 100% UHMWPE.
The cracker is also constructed from UHMWPE to ensure consistency in performance and durability.

We believe that any compromise in materials inevitably leads to a compromise in performance.
For this reason, only proven, top-tier materials are used in every structural and functional element of the sling.

For specific information on the materials used in Greenline Slings, please refer to Materials.

Toward a Physically Ideal Sling

When personal preference is set aside and a sling is examined purely through physics,
the requirements of an ideal design become clear:

Lighter mass improves energy transfer efficiency
Reduced air resistance minimizes energy loss
Split pouch that can accommodate a wide range of projectiles
The sling should not stretch even when strong tension is applied
The sling should be simple and easy to carry at all times
The structure must endure repeated use without deformation

Greenline Sling is the result of long-term research and experimentation aimed at meeting all of these conditions simultaneously in a single design.

Almost as If It Doesn’t Exist

The cords of Greenline Sling are extremely thin,
and the total weight of the sling is approximately 10 grams.

We believe a physically ideal sling should feel as though it barely exists.

Between the finger loop on your hand and the projectile in the pouch,
there should seem to be no mass, no resistance—
only an almost magical attraction connecting the two.

The sling disappears,
and only the motion of the projectile remains.

Eliminating Structural Weak Points

To maximize durability and aerodynamic efficiency,
the sling body contains no knots whatsoever.

In addition, all cut ends of UHMWPE fibers within the sling body are intentionally concealed and never exposed to the outside.

The rear webbing of the pouch is heat-treated,
finished using a double fold hem technique,
and fully locked in place through retention cord splicing.
The cut ends of every fiber in the pouch, retention cord, and release cord
are hidden deep within the structure—
invisible and unreachable from the outside.

This approach structurally eliminates potential initiation points for wear and failure.

Multi-layer Friction-Based Release System

Instead of a traditional release knot,
Greenline Sling employs a proprietary multi-layer friction-based release grip system.

This system is engineered to provide maximum projectile retention with minimal bulk,
ensuring a secure hold without unnecessary mass or protrusion.
By reducing the volume and turbulence at the release point,
air resistance is minimized, directly improving overall slinging efficiency and responsiveness.

The UHMWPE cracker is firmly locked to the release grip end, providing consistent release feedback and increased sling life through shock absorption.

Reinforcement Where Wear Is Most Severe

The pouch–release junction, where repeated contact with the projectile causes the greatest wear,
is one of the most critical areas of a sling.

Greenline Sling reinforces this spliced section with titanium alloy rings,
structurally preventing the projectile from making direct contact with the spliced UHMWPE fibers.

As a result, relatively vulnerable fibers are shielded,
and friction is concentrated on a material specifically chosen for its extreme wear resistance.

This solution delivers maximum protection with minimal added weight,
significantly extending the lifespan of the sling
while preserving its low mass and aerodynamic performance.