Telescoping Box Size Chart: Adjustable-Length Boxes for Long Items
A telescoping box is an inner and an outer half slotted box that slide together, so one pair covers item lengths from the length of one piece to almost twice that. The chart lists every stocked pair by cross-section with its adjustable range, the length plus girth at full extension, the carrier surcharge lines it crosses, and which pair to start from for golf clubs, lamps, rods, skis and art.
How telescoping boxes work
A telescoping box is two half slotted boxes, an inner and an outer, each open at one end. The inner slides into the outer, and the overlap sets the finished length: fully nested the box is as long as one piece, and pulled out to the recommended 8 inches of overlap it is nearly twice as long. One pair therefore covers a range of item lengths, which is why they are stocked in a handful of cross-sections and lengths rather than the hundreds of fixed sizes that regular boxes need. Where the two halves overlap the box is double thickness, and that overlap is the strongest part of the box.
Stocked inner and outer pairs
Inner boxes are listed by their inside dimensions; the matching outer is half an inch larger on each cross-section side so it slides over the inner. Pairs are sold separately so a shipper with mostly 60 inch loads can buy more outers, or use a single inner as a lidless tray for storage.
| Cross-section (inside) | Inner box | Outer box | Adjustable length | L + G at full extension | Carrier lines |
|---|---|---|---|---|---|
| 37 x 4 in | 37 x 4 x 30 inner | 37.5 x 4.5 x 30 outer | 30 to 52 in | 136 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 14 x 14 in | 14 x 14 x 40 inner | 14.5 x 14.5 x 40 outer | 40 to 72 in | 130 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 16 x 16 in | 16 x 16 x 40 inner | 16.5 x 16.5 x 40 outer | 40 to 72 in | 138 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 18 x 18 in | 18 x 18 x 40 inner | 18.5 x 18.5 x 40 outer | 40 to 72 in | 146 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 20 x 20 in | 20 x 20 x 40 inner | 20.5 x 20.5 x 40 outer | 40 to 72 in | 154 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 4 x 4 in | 4 x 4 x 48 inner | 4.5 x 4.5 x 48 outer | 48 to 88 in | 106 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 6 x 6 in | 6 x 6 x 48 inner | 6.75 x 6.75 x 48 outer | 48 to 88 in | 115 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 8 x 8 in | 8 x 8 x 48 inner | 8.75 x 8.75 x 48 outer | 48 to 88 in | 123 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 10 x 10 in | 10 x 10 x 48 inner | 10.5 x 10.5 x 48 outer | 48 to 88 in | 130 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 12 x 4 in | 12 x 4 x 48 inner | 12.5 x 4.5 x 48 outer | 48 to 88 in | 122 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 12 x 12 in | 12 x 12 x 48 inner | 12.5 x 12.5 x 48 outer | 48 to 88 in | 138 in | L+G shown for carrier dimensional check; longest side over 48 in |
| 10 x 6 in | 10 x 6 x 57 inner | 10.5 x 6.5 x 57 outer | 57 to 106 in | 140 in | L+G shown for carrier dimensional check; longest side over 96 in |
| 24 x 8 in | 24 x 8 x 57 inner | matching outer not identified | not calculated | not calculated | matching outer not identified |
| 4 x 4 in | 4 x 4 x 72 inner | 4.5 x 4.5 x 72 outer | 72 to 136 in | 154 in | L+G shown for carrier dimensional check; longest side over 96 in |
| 6 x 6 in | 6 x 6 x 72 inner | 6.5 x 6.5 x 72 outer | 72 to 136 in | 162 in | L+G shown for carrier dimensional check; longest side over 96 in |
| 8 x 8 in | 8 x 8 x 72 inner | 8.5 x 8.5 x 72 outer | 72 to 136 in | 170 in | Over 165 in L+G: outside cited UPS Small Package/FedEx Ground parcel limits; longest side over 96 in |
| 10 x 10 in | 10 x 10 x 72 inner | 10.5 x 10.5 x 72 outer | 72 to 136 in | 178 in | Over 165 in L+G: outside cited UPS Small Package/FedEx Ground parcel limits; longest side over 96 in |
| 12 x 12 in | 12 x 12 x 72 inner | 12.5 x 12.5 x 72 outer | 72 to 136 in | 186 in | Over 165 in L+G: outside cited UPS Small Package/FedEx Ground parcel limits; longest side over 96 in |
Adjustable telescoping tubes
Two-piece tubes work the same way for rolled prints, blueprints, rods and extrusions and weigh less than a box of the same length.
What fits which pair
| Item | Typical length | Cross-section needed | Pair to start from |
|---|---|---|---|
| Golf clubs (driver, boxed) | 45 to 48 in | 6 x 6 to 8 x 8 in | 6 x 6 x 40 or 8 x 8 x 48 pair |
| Floor lamp, curtain rod, closet rod | 60 to 84 in | 6 x 6 to 10 x 10 in | 6 x 6 x 48 or 10 x 10 x 48 pair |
| Fishing rod (two piece) | 48 to 84 in | 4 x 4 to 6 x 6 in | 4 x 4 x 48 pair or adjustable tube |
| Skis, snowboard, hockey sticks | 60 to 78 in | 8 x 4 to 12 x 6 in | 12 x 4 x 48 or 10 x 6 x 57 pair |
| Framed art, mirrors, posters in tubes | 36 to 72 in | 4 x 4 to 12 x 4 in | 12 x 4 x 48 pair or mirror box |
| Long machine parts, extrusions, pipe | 48 to 120 in | 4 x 4 to 12 x 12 in | 12 x 12 x 72 pair for the longest loads |
Carrier limits for long boxes
Use the calculated length plus girth and longest side as dimensional checks, then confirm the current service terms before tendering a shipment. The cited UPS Small Package guidance and FedEx Ground guidance state a 165 inch length-plus-girth maximum. A 12 x 12 in pair extended to 88 inches measures 138 inches length plus girth. The carrier size and weight limits page has the full table, and the DIM weight chart shows why a long, thin box is billed by volume.
Packing a telescoping box
- Pad the ends. Long items load the closed ends on impact; put 2 inches of foam or crumpled kraft at each end before the item goes in.
- Immobilize. Wrap the item so it cannot slide; a rod that travels 4 inches inside a box punches through the end.
- Set the overlap. Slide the outer over the inner to the item length plus end padding, keeping at least 8 inches of overlap.
- Tape the joint. One band of tape around the box where the outer ends, then an H-seal on each closed end.
- Support the middle. Boxes over 72 inches sag when lifted from the ends; add a corrugated pad or a second inner along the bottom for heavy items.
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Frequently asked questions
What is a telescoping box?
A two-piece box (inner and outer half slotted containers) that slides together to any length between the length of one piece and roughly twice that, used for long items like lamps, rods, golf clubs and art.
How long can a telescoping box be?
A 48 inch pair adjusts from 48 to about 88 inches with 8 inches of overlap; a 72 inch pair reaches about 136 inches. Before choosing a shipping service, compare the calculated length plus girth with current service-specific limits; the linked UPS Small Package and FedEx Ground guidance list 165 inches.
Do I need to buy the inner and outer separately?
Yes, they are stocked as separate products so you can buy in the ratio your loads need; one of each makes one adjustable box.
What size telescoping box for golf clubs?
A 6 x 6 in or 8 x 8 in cross-section pair 40 to 48 inches long; a boxed driver is about 46 inches, so a 48 inch pair nested nearly fully covers it with end padding.
Is a telescoping box strong enough to ship without a tube inside?
The overlapped section is double thickness, but select and validate the packaging for the item's weight, geometry, cushioning and current carrier terms. Add internal support where needed so the load does not bear on one box wall.