Travel Elite 2-in-1 Lightweight Backpack 21L

Waterfly Travel Elite 2-in-1 Lightweight Backpack 21L is a 21L, 0.53kg1.2lb travel backpack measuring 43.2×26.7×20.3cm17×10.5×8in. It fits the carry-on size limit of 32 of 36 major airlines and the personal-item limit of 0 of 26. Under the seat, its 20.3cm8in side is over the 20cm7.9in limit at 15 of the 26 airlines it misses. Specs from waterflyshop.com, checked October 2026.

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Volume: 21Lfixed size
Weight: 0.53kg1.2lb1.2lb0.53kg
Carry-on: 32/36airlines fit it
Personal item: 0/26under-seat limits

Dimensions: 43.2×26.7×20.3cm17×10.5×8in 17×10.5×8in43.2×26.7×20.3cm
Price: $22.99 as of October 2026
Laptop: n/a
Opening: Zippered main compartment
Warranty: 10 years 10-year limited warranty for registered members buying direct; guests 3 years.
Compartments: n/a
Bottle pockets: 2

Water-resistant
Sternum strap

Material: Tear-resistant, water-resistant nylon, polyester lining

Folds into its own pocket
Detachable front pocket doubles as a crossbody bag
Separate waterproof wet pocket for damp clothes

Last checked: 2026-10. Prices and specs may have changed.

Does the Waterfly Travel Elite 2-in-1 Lightweight Backpack 21L fit airline carry-on limits?

Draw against

Too bigToo big on Ryanair. cabin bag 55×40×20cm21.5×15.5×8in · under the seat 40×30×20cm15.5×12×8in. Bag in cminches, turned to fit.

Flag as a tight fit undercm spare

Airline	Carry-on	Personal item	Cabin-bag weight
Air Arabia	Too bigToo big	Too bigToo big	6.5kg to pack (of 7kg)14.3lb to pack (of 15.4lb)
Air CanadaCabin bag not on every fare	FitsFits	Too bigToo big	No published limitNo published limit
Air FranceCabin bag not on every fare	FitsFits	Too bigToo big	11.5kg to pack (of 12kg shared with personal item)25.4lb to pack (of 26.5lb shared with personal item)
Air India	Too bigToo big	No published limit	6.5kg to pack (of 7kg)14.3lb to pack (of 15.4lb)
AirAsia	FitsFits	Too bigToo big	6.5kg to pack (of 7kg shared with personal item)14.3lb to pack (of 15.4lb shared with personal item)
Alaska Airlines	FitsFits	No published limit	No published limitNo published limit
Allegiant AirCabin bag not on every fare	FitsFits	Too bigToo big	No published limitNo published limit
American Airlines	FitsFits	Too bigToo big	No published limitNo published limit
ANA (All Nippon Airways)	FitsFits	Too bigToo big	9.5kg to pack (of 10kg shared with personal item)20.9lb to pack (of 22lb shared with personal item)
AviancaCabin bag not on every fare	FitsFits	No published limit	9.5kg to pack (of 10kg)20.9lb to pack (of 22lb)
British Airways	FitsFits	Too bigToo big	No published limitNo published limit
Cebu Pacific	FitsFits	Too bigToo big	9.5kg to pack (of 10kg shared with personal item)20.9lb to pack (of 22lb shared with personal item)
Delta Air Lines	FitsFits	No published limit	No published limitNo published limit
easyJetCabin bag not on every fare	FitsFits	Too bigToo big	14.5kg to pack (of 15kg)32lb to pack (of 33.1lb)
Emirates	Tight fit (1.7cm spare)Tight fit (0.7in spare)	No published limit	6.5kg to pack (of 7kg)14.3lb to pack (of 15.4lb)
Frontier AirlinesCabin bag not on every fare	FitsFits	Too bigToo big	15.4kg to pack (of 15.9kg)34lb to pack (of 35.1lb)
Gol Linhas Aereas	FitsFits	No published limit	9.5kg to pack (of 10kg)20.9lb to pack (of 22lb)
IndiGo	FitsFits	No published limit	6.5kg to pack (of 7kg)14.3lb to pack (of 15.4lb)
JetBlue Airways	FitsFits	Too bigToo big	No published limitNo published limit
KLMCabin bag not on every fare	FitsFits	Too bigToo big	11.5kg to pack (of 12kg shared with personal item)25.4lb to pack (of 26.5lb shared with personal item)
LATAM Airlines	FitsFits	Too bigToo big	11.5kg to pack (of 12kg)25.4lb to pack (of 26.5lb)
LufthansaCabin bag not on every fare	FitsFits	Too bigToo big	7.5kg to pack (of 8kg)16.5lb to pack (of 17.6lb)
Norwegian Air ShuttleCabin bag not on every fare	FitsFits	Too bigToo big	9.5kg to pack (of 10kg shared with personal item)20.9lb to pack (of 22lb shared with personal item)
Qantas	FitsFits	No published limit	6.5kg to pack (of 7kg shared with personal item)14.3lb to pack (of 15.4lb shared with personal item)
Qatar Airways	FitsFits	No published limit	6.5kg to pack (of 7kg)14.3lb to pack (of 15.4lb)
RyanairCabin bag not on every fare	Too bigToo big	Too bigToo big	9.5kg to pack (of 10kg)20.9lb to pack (of 22lb)
SAS	FitsFits	Too bigToo big	7.5kg to pack (of 8kg)16.5lb to pack (of 17.6lb)
Singapore Airlines	FitsFits	Too bigToo big	6.5kg to pack (of 7kg)14.3lb to pack (of 15.4lb)
Southwest Airlines	FitsFits	No published limit	No published limitNo published limit
Turkish Airlines	FitsFits	Too bigToo big	7.5kg to pack (of 8kg)16.5lb to pack (of 17.6lb)
United AirlinesCabin bag not on every fare	FitsFits	Too bigToo big	No published limitNo published limit
Vietjet Air	FitsFits	Too bigToo big	6.5kg to pack (of 7kg shared with personal item)14.3lb to pack (of 15.4lb shared with personal item)
VolarisCabin bag not on every fare	FitsFits	Too bigToo big	9.5kg to pack (of 10kg)20.9lb to pack (of 22lb)
VuelingCabin bag not on every fare	Too bigToo big	Too bigToo big	9.5kg to pack (of 10kg)20.9lb to pack (of 22lb)
WestJetCabin bag not on every fare	FitsFits	Too bigToo big	No published limitNo published limit
Wizz AirCabin bag not on every fare	FitsFits	Too bigToo big	9.5kg to pack (of 10kg)20.9lb to pack (of 22lb)

Compared in any orientation against each airline's published size limit. A tight fit has under 2cm to spare, so a packed soft bag may not pass a sizer. Set it to 0 to turn the warning off. Weight is what the airline allows in the cabin minus this bag's empty 0.53kg1.2lb. Limits and sources. Own a different bag? Check it against every airline.