Press seal bags give commercial operators a resealable plastic closure that opens and closes by hand, with no heat, tape or clips required. For businesses across food, medical, industrial, retail and agriculture, that simple press-to-close strip delivers repeatable access, moisture and dust protection, clear product visibility and made-to-spec sizing. Below are the main benefits, the right way to specify gauge and size, and how each sector puts these bags to work.

What are press seal bags?

A press seal bag is a plastic bag with two matching ribs along the opening that click together when pressed and pull apart when you need the bag open again. The seal reforms every time, so the same bag can be closed and reopened many times over. These are also known as zip seal bags, zip lock bags, snap lock bags, grip seal bags and clip lock bags, and the closure works the same way across all of them.

Most are made from low density polyethylene (LDPE), a clear, flexible film that holds a firm seal and shows the contents through the wall. Plastpack manufactures its own press seal bags in Australia, extruding the film, printing it and forming the bags in-house rather than buying finished stock from a third party.

The top benefits of press seal bags for storage and packaging

A secure closure you can open and reseal by hand

The press-to-seal strip removes the need for tape, heat sealers or twist ties. Staff on a packing line, at a workbench or at a service counter can close a pack in a second and reopen it just as fast. For any workflow that needs repeated access to the same contents, such as sample kitting, parts picking or repackaged retail goods, reusable press seal bags keep the pack intact through every open and close.

A barrier against moisture, dust and contamination

A firm seal creates a physical barrier that holds out moisture, dust and airborne contaminants. Contents stay in the condition they left your facility in, which matters for hardware that corrodes, powders that clump, documents that stain and food that needs to stay clean. Resealable storage bags protect goods on the shelf, in transit and during handling, so fewer items are written off along the way.

Clear film that keeps contents visible

Clear press seal bags let staff and customers identify contents at a glance without opening the pack. That speeds up stocktakes, order picking and quality checks, and it presents repackaged product well at point of sale. Where a job calls for an opaque or coloured film instead, Plastpack can produce that to order.

Durability matched to the job

Gauge, measured in microns, sets how much a bag resists puncture and how well it holds its seal under load. A light 50 micron bag suits general storage and small, smooth items. A heavier 75 micron film stands up to sharp edges, heavier contents and frequent handling, which is why engineering and industrial buyers reach for it. If you are unsure which gauge fits your contents, our guide to choosing the right plastic bag thickness walks through it.

On-bag labelling with write-on panels

A write-on panel version carries a matte white strip you can mark by hand. That is useful anywhere batch numbers, dates, contents or specimen details need to be recorded directly on the bag, without a separate label. It keeps identification with the pack from the moment it is filled.

Custom sizing and printing for your product

Standard sizes cover most jobs, but a bag cut to your exact product reduces excess film, packs neater and looks considered on the shelf. As the manufacturer, Plastpack produces bags to your required size, thickness and seal, with up to six-colour printing for branding, handling marks or compliance text. The minimum order for a custom size is 10,000 units.

Reliable bulk supply from held stock

Held film stock keeps lead times short, so bulk orders can be manufactured and dispatched Australia-wide without a long wait. For businesses that reorder on a schedule or scale volumes through peak periods, consistent bulk and wholesale supply keeps packing lines running and shelves stocked.

Benefits at a glance

Choosing the right press seal bag for your sector

Food and beverage. Food-grade press seal bags suit dry goods, portioned ingredients, sample packs and resealable retail lines. Food-contact use calls for the correct food-grade product, so specify food use at the enquiry stage and Plastpack will supply bags made to the relevant food safety requirements.

Medical, clinical and pathology. Sealable bags are used for specimen handling, sample transport and controlled storage. For regulated clinical use, specify against the relevant standards and procedures, and follow qualified handling protocols for the materials involved. Plastpack manufactures to those requirements rather than supplying general-purpose stock.

Industrial and engineering. Fixings, components, blades and hardware need a bag that resists puncture and holds its seal through handling. A 75 micron gauge is the usual choice here, and a printed or write-on version helps track parts through assembly and dispatch.

Retail and eCommerce. Clear bags present product cleanly and let customers reseal after opening, which suits repackaged goods, multi-packs and accessories. Custom print turns a plain pack into a branded one.

Agriculture and horticulture. Sample bags, seed storage and small parts on farms and in nurseries all benefit from a resealable, weather-resistant closure. Match the gauge to the roughness of the contents.

Logistics and warehousing. Kitting, returns and small-parts storage move faster when each pack seals and reopens without tools, and clear film keeps contents identifiable through the pick and pack process.

Gauge and specification guide

Sizes are specified as opening width by depth in millimetres, with depth measured from the seal. If your contents fall between two gauges, step up rather than down, since a bag that fails in transit costs far more than the film saved.

Recyclability and responsible specification

Standard press seal bags are made from LDPE, which is a recyclable polyethylene, and Plastpack offers biodegradable and degradable options on selected lines where they genuinely apply. The largest environmental gain, though, often comes from specifying correctly in the first place: the right gauge and size means less film used, fewer failed packs and less waste through the supply chain. If you are weighing up film types, our comparison of LDPE and HDPE plastic films explains where each one fits. We do not claim a product is recyclable or biodegradable unless that specific line actually is.

Why buy press seal bags from an Australian manufacturer

Many suppliers ranking for press seal bags hold third-party stock and resell it. Plastpack extrudes its own film, prints it and forms the bags at its Australian facility, with quality control and dispatch under one roof. That means direct control over thickness, sizing and print, consistent batches run to run, and film held on site for fast turnaround. You deal with the business that actually makes the bag, so specification advice, sampling and custom runs come from the people running the extruder and the press.

For general-purpose resealable lines you can also compare our zip lock bags and standard plain poly bags, or ask our team to recommend the right product for your contents and volume.

Frequently asked questions

What are press seal bags used for?

They are used for commercial storage, sample handling, small parts, food packing and resealable retail packs. The press-to-seal strip opens and closes by hand with no heat or tape, so contents stay secure through repeated access.

What is the difference between press seal bags and zip lock bags?

They are the same product under different names, including zip seal, snap lock, grip seal and clip lock bags. Each uses an interlocking strip along the opening that presses closed and pulls apart to reseal.

Which thickness of press seal bag do I need?

Choose 50 micron for general storage and light, smooth contents. Step up to 75 micron for sharp, heavy or frequently handled items, since the thicker film resists puncture and holds its seal under load.

Are press seal bags food safe?

Plastpack manufactures food-grade press seal bags for food-contact applications, made to the relevant food safety requirements. Specify food use when you enquire so the correct product is supplied.

Can I order custom-printed or custom-sized press seal bags?

Yes. As the manufacturer, Plastpack produces bags to your size, thickness and seal, with up to six-colour printing and write-on panels available. The minimum quantity for a custom size is 10,000 units.