Spark Plug Boxes.

Each plug sits in its own die-cut cell, isolated from its neighbours and from the box walls. The ceramic insulator chips where it meets the metal shell, and the crack is often invisible until the plug is fitted, which is when the labour cost multiplies. Individual cells mean no plug-to-plug contact however the case is handled.

We do not pack sets loose, for exactly that reason.

For premium and iridium plugs, where the shock absorption of a formed cradle earns its cost. Pulp cradles are moulded to the plug profile and give under impact, which flat board cannot do. Standard copper plugs are well served by die-cut cells in E-flute or boxboard.

Both inserts also keep a knock away from the pre-set electrode gap, which a drop can alter without any visible damage.

Four, six and eight, following cylinder count, plus a single-plug carton for trade counters. The engine decides how many plugs are sold together, so the insert is cut to that count and the outer carton follows. Singles are sized for replacement sales and are built to scan without being turned over.

Reinforced corners go on every format because a dropped box concentrates its impact there.

The part number, large and high-contrast on more than one face. It is the highest-value element on the pack, since a fitter picks by number and checks the pre-set gap figure next. The application panel lists vehicle fitment, and the barcode zone is sized to scan first time from the rack.

Retail cartons run full CMYK on boxboard. Trade supply uses one or two colour flexo on E-flute, which is cheaper and still legible.

A four-pack runs about 6 by 3 by 4 inches, and a single is around 1.5 by 1.5 by 4 inches. The cell pitch is set from the plug hex size and the insulator length, with clearance so the terminal nut never touches the cell wall. Send the plug dimensions and we cut the insert to them.

Orders begin at 500 cartons per size and print. The die-cut insert comes on the same order without its own minimum. Tiered pricing kicks in above 1,000 and runs to 100,000, which suits aftermarket volumes.

Part number changes within a range are handled as artwork versions on the same dieline.

Most jobs ship in 7 to 10 business days after proof approval. Rush runs are 5 to 7 business days. Samples come in 5 to 7 business days and let you drop-test the insert with real plugs before committing to the run.

The sample cost is offset against the production invoice, and the dieline is drawn at no cost.

E-flute corrugated outers with reinforced corners take the stacking pressure of a parts warehouse. Racking loads are real in this trade, and the insert carries some of that compression as well, since the cells brace the walls. For retail-facing cartons on folding boxboard, the insert does the protecting and the outer case does the stacking.

Both boards are recyclable, and the pulp insert goes in the same stream.