Stretch film selection often gets reduced to "which micron" — but underneath that is a real trade-off between two distinct properties that don't always move together.
Cling force
How tightly and consistently the film grips itself and the load as it's wrapped. High cling force matters for:
- Load stability during transit — preventing shifting or loosening
- Clean, tight-looking pallets (relevant for customer-facing or export shipments)
- Uniform, regularly-shaped loads where consistent tension is achievable
Cast film (see Cast vs Blown) generally offers stronger, more consistent cling.
Puncture resistance
How well the film resists tearing when it meets a sharp edge, corner, or irregular protrusion on the load. High puncture resistance matters for:
- Mixed-SKU pallets with inconsistent shapes
- Loads with sharp corners, metal edges, or protruding parts
- Any situation where a single tear could compromise the whole wrap
Blown film generally offers meaningfully better puncture resistance than cast film at the same gauge.
Why this is a genuine trade-off
These two properties don't scale together — a film optimized purely for cling tends to be more vulnerable to punctures, and a film optimized for puncture resistance tends to have a slightly different (sometimes hazier) surface that clings less aggressively. There's no single "best" film — the right choice depends on which failure mode your actual loads are more prone to.
Practical guidance
- Uniform, boxed pallets, no sharp edges → prioritize cling force, cast film
- Mixed SKUs, irregular shapes, sharp corners → prioritize puncture resistance, blown film
- Genuinely unsure → 20 micron cast film is a reasonable middle-ground default; see the Micron Guide
Describe your typical pallet to PackGPT and get a direct film-type recommendation. Talk to PackGPT.