Covestro PC Set-Moulded Clamshells
Four graduated Covestro polycarbonate or ABS+PC shells engineered to nest Russian-doll style from 20 Inch (39 L) to 28 Inch (85 L) while resisting -40 °C to 120 °C thermal swings.
Building a four-piece luggage family that nests cleanly from 20 Inch up to 28 Inch requires a different structural balance than a standalone cabin case. The Captain Aluminum Frame line pairs thermoformed Covestro polycarbonate (or a custom-specified ABS+PC compound) clamshells with an extruded 5052/6061 aluminium-magnesium alloy perimeter frame. Because the shell body is polymer rather than solid metal (unlike our stamped full-aluminium AURA Collection), the 20-inch carry-on holds its net weight to 4.04 kg (39 L capacity, 0.104 kg/L specific ratio) while retaining the rigid mouth closure of a metal-framed suitcase.
In a four-size set, the 26-inch Medium-Plus (73 L, 5.35 kg) and 28-inch Large (85 L, 6.3 kg) checked cases endure severe baggage-handling stack pressures at the bottom of aircraft cargo holds. In our Bogor test lab, 535–660 mm cases (20" and 24") are subjected to 40 kg of continuous static compression for 4 hours, while 685–835 mm cases (26" and 28") must sustain 60 kg for 4 continuous hours without frame buckling. The extruded 5052/6061 closure channel achieves a Brinell hardness of ≥ 40 HWB under ISO 6506 / ASTM E10, keeping the tongue-and-groove seal aligned so the dual TSA mechanical latches click shut smoothly even when the 85 L case is fully packed.
To protect the shell vertices during conveyor drops, four stamped 5052/6061 alloy corner caps are mechanically riveted over the top and bottom corners of the Covestro PC body. Inside, dual compression straps and mesh divider panels keep garments flat while leaving enough internal clearance for the smaller suitcase to nest inside the next size up during ocean transit (exact lining denier and foam thickness are confirmed per order).
Four graduated Covestro polycarbonate or ABS+PC shells engineered to nest Russian-doll style from 20 Inch (39 L) to 28 Inch (85 L) while resisting -40 °C to 120 °C thermal swings.
External riveted 5052/6061 aluminium-magnesium corner caps absorb 900 mm room-temperature and 90 cm cold (-12 °C, 4 h) impacts across all four set sizes.
The riveted 5052/6061 perimeter frame (≥ 40 HWB Brinell hardness) sustains 40 kg (20"/24") and 60 kg (26"/28") continuous 4-hour static compression tests without mouth distortion.
Identical 360° SilentMove dual-spinner wheel assemblies across the 20, 24, 26, and 28 inch sizes simplify spare-parts stocking and pass 8+2+2 km drum wear tests (≤ 2 mm).
Precision ball-bearing swivel heads and TPE tyres keep rolling noise under 40 dB even when pulling two nested suitcases simultaneously through terminal concourses.
Most Asian OEM factories only tool 20-inch, 24-inch, and 28-inch moulds, leaving a 25 L gap between medium and large checked bags. Only two lines in our Bogor factory — the Captain Aluminum Frame and the full-aluminium AURA Collection — include the 26-inch Medium-Plus mould. On the Captain Aluminum Frame ladder, capacity progresses in balanced increments: 39 L (20"), 57 L (24", +18 L), 73 L (26", +16 L), and 85 L (28", +12 L). That 26-inch case (69.1 × 46.0 × 26.4 cm, 5.35 kg net) is the most valuable piece in retail set merchandising: it delivers 73 L of 10-day packing capacity while staying 0.95 kg lighter and 4.8 cm shorter than the 28-inch trunk, preventing airline overweight-bag fees for travellers who find a 57 L medium case too small.
Notice how volumetric efficiency improves as you move up the ladder: the 20-inch cabin case has a specific weight ratio of 0.104 kg/L (4.04 kg ÷ 39 L), dropping to 0.084 kg/L on the 24-inch, and reaching peak efficiency at 0.073 kg/L on the 26-inch Medium-Plus and 0.074 kg/L on the 28-inch Large. Note that the metric external and packed dimensions below (H × W × D axis order) are direct × 2.54 metric conversions from the original inch specification tables on this page:
| Size Step | External Dimensions (H × W × D, cm) | Packed Carton (cm) | Capacity (L) | Net Weight (kg) | Gross Weight (kg) | Specific Ratio (kg/L) |
|---|---|---|---|---|---|---|
| 20 Inch (Carry-On) | 55.9 × 36.1 × 23.1 cm | 39.9 × 23.9 × 62.0 cm | 39 L | 4.04 kg | 4.99 kg | 0.104 kg/L |
| 24 Inch (Medium Checked) | 64.0 × 41.9 × 24.9 cm | 45.0 × 27.4 × 69.1 cm | 57 L | 4.78 kg | 5.95 kg | 0.084 kg/L |
| 26 Inch (Medium-Plus) | 69.1 × 46.0 × 26.4 cm | 49.5 × 28.4 × 74.4 cm | 73 L | 5.35 kg | 6.65 kg | 0.073 kg/L |
| 28 Inch (Large Checked) | 73.9 × 48.5 × 26.9 cm | 51.6 × 29.5 × 79.5 cm | 85 L | 6.3 kg | 7.75 kg | 0.074 kg/L |
Retail buyers building a physical store display or a multi-SKU marketplace storefront need both core business shades and visual traffic-drivers. The Captain Aluminum Frame palette spans 6 distinct colours: three commercial anchors (Black, Grey, White) and three lifestyle statement tones (Blue, Green, Pink). Rather than forcing every colour into all four sizes, savvy retail merchandisers use this 6-colour palette to tier their shelf presentation: stocking Black, Grey, and Blue across the full 20/24/26/28-inch set, while running Green, Pink, and White in 20-inch carry-ons and 20"+24" two-piece duos.
Across all six shades, pigment masterbatch is compounded directly into the Covestro polycarbonate / ABS+PC sheet extrusion so surface scratches do not expose a contrasting base layer. The 5052/6061 aluminium-magnesium alloy frame, latch housings, and four riveted corner caps are finished with a 10–12 μm anodised oxide film. Tested to ISO 9227 / ASTM B117 (16-hour neutral salt spray with ≤ 3 corrosion spots and ≤ 1 mm² spot area) and rated for thermal stability from -40 °C to 120 °C, the hardware retains its metallic lustre in humid tropical warehouses and coastal sea-freight containers.
When importing multi-size luggage sets, packaging engineering directly determines both your landed sea-freight cost and your warehouse receiving speed. Because the 20" (55.9 × 36.1 × 23.1 cm), 24" (64.0 × 41.9 × 24.9 cm), 26" (69.1 × 46.0 × 26.4 cm), and 28" (73.9 × 48.5 × 26.9 cm) shells step up progressively in height, width, and depth, our Bogor packing line can pack them in Russian-doll nested configurations (nested set) inside the 51.6 × 29.5 × 79.5 cm (28-inch) master export carton, separated by PE dust bags and EPE foam corner interleaves.
For private-label set programs at the 100-piece per SKU minimum, we customize the entire set presentation:
Because our factory MOQ is 100 pcs per colour × size SKU, ordering all 6 colours across all 4 sizes at once would mean 24 SKUs (2,400 suitcases). Most brand buyers and regional distributors do not start with 24 SKUs — instead, they structure their opening container around proven set ratios that match their sales channel:
Produced at our Bogor factory (group manufacturing luggage since 2011 — 14 years — and Indonesia plant operating since 2025 with 75 staff and 80,000 units/month capacity), samples ship in 7–15 working days and bulk orders complete in 25–55 working days after deposit and sample approval. Tiered pricing, payment terms, and Incoterms are confirmed per order.
How many pieces make the best-selling retail luggage set across 20, 24, 26, and 28 inch sizes? For e-commerce and hypermarket bundles, the 3-piece nested set (20" 39 L + 24" 57 L + 28" 85 L) is the highest-volume configuration. For specialty travel retailers and urban apartment buyers with limited storage space, a 2-piece nested duo pairing the 20-inch carry-on (39 L, 4.04 kg) inside the 26-inch Medium-Plus case (73 L, 5.35 kg) sells strongly because the 26-inch size bridges 1-week and 2-week trips.
How much sea-freight volume does Russian-doll nesting (nested set) save? When shipped individually, the four cartons (20", 24", 26", and 28") occupy 0.059 + 0.085 + 0.105 + 0.121 = 0.370 CBM. When the smaller sizes are nested inside the 28-inch master carton (51.6 × 29.5 × 79.5 cm, 0.121 CBM), total carton volume per set drops by up to 67%, cutting ocean freight cost per unit by more than half.
What is the real difference between the 24-inch Medium and the 26-inch Medium-Plus suitcase? The 24-inch case measures 64.0 × 41.9 × 24.9 cm, weighs 4.78 kg, and holds 57 L (0.084 kg/L). The 26-inch Medium-Plus steps up to 69.1 × 46.0 × 26.4 cm, weighs 5.35 kg, and holds 73 L (0.073 kg/L) — adding 16 L of interior volume (+28%) for only 0.57 kg of additional weight.
If we order all 6 colours in a nested set, how is the 100-piece MOQ calculated? Our MOQ of 100 pcs is calculated per individual colour × size combination. A 3-piece nested set (20/24/28") in 1 colour equals 100 sets (300 individual suitcases across 3 SKUs). If you want all 6 colours in a 3-piece set, that totals 600 sets (1,800 suitcases across 18 SKUs).
Are the corner protectors on the Captain Aluminum Frame made of metal or plastic? All four corner caps are stamped from 5052/6061 aluminium-magnesium alloy (the same alloy family as the perimeter closure frame), finished with a 10–12 μm anodised layer, and mechanically riveted through the Covestro polycarbonate shell to pass 900 mm room-temperature and 90 cm -12 °C drop tests.
Do not confuse this 6-colour Captain Aluminum Frame line with the 3-colour Captain Zipperless Aluminum Frame Carry-On — they are two independent product lines built on different moulds for different commercial buyers. This Captain Aluminum Frame line is built for multi-size set merchandising: it offers all four sizes (20 / 24 / 26 / 28 Inch, 39–85 L), 6 colours (including Blue, Green, Pink, and White), and lighter 20-inch cabin weight (4.04 kg vs 4.85 kg). By contrast, the Captain Zipperless line omits the 26-inch size and limits colours to 3 (Black, Grey, Silver), using a deeper cabin mould (38 × 23 × 54 cm) to pack 48 L into a single-SKU 20-inch carry-on.
Compared with the Voyager Zipperless Aluminum Frame Carry-On (which also skips the 26-inch step and focuses on a fine-rib shell in 4 metallic neutrals at 4.38 kg / 39 L for 20-inch), Captain Aluminum Frame gives you 2 additional bright retail shades and the 73 L 26-inch step. And if you need the same four-step 20/24/26/28-inch size ladder in a 100% metal body rather than a Covestro PC shell, step up to our AURA Collection (stamped 5052/6061 full aluminium, 3.7–5.7 kg, 45–105 L, 8 colours). Compare all four collections on our main products page.
Order the Captain Aluminum Frame line in 20, 24, 26, and 28 inch sets across 6 colours from our Bogor factory — MOQ 100 pcs per colour-size SKU, 7–15 day sampling, and 25–55 day bulk delivery.