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Knack Bags

Series 2 Small Expandable Backpack

Track unexpanded vs expanded dimensions. | Official Knack page shows 17L unexpanded, 27L expanded, 17 x 12.5 x 5 in, and 2 lb 6 oz. | Launch-only softness, compressibility, opening, bottle-pocket, and price fields inferred from category and model.

Dimensions
17 x 12.5 x 5 in
Capacity
17 L
Weight
2.38 lb
Last reviewed
2026-05-29
Audited dimensions

Bag data

Audited dimensions
Last reviewed
2026-05-29
Dimension confidence
high
Primary source
manufacturer

Fit by airline

Airline fit results

Carry-on

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.

Visual sizer

Bag vs airline rule

Fits

Fits. Tightest spare room: 2.9 in.

Dimension-only silhouette
Scaled fit visualizationFits. Tightest spare room: 2.9 in.Bag size17 x 12.5 x 5 inRule size21.7 x 15.7 x 7.9 inRule width 15.7 inRule length 21.7 inBag width 12.5 inBag length 17 inDepth: Bag 5 in / Rule 7.9 in

Fits. Tightest spare room: 2.9 in.

Height

Spare room +4.7 in

Bag 17 in / Rule 21.7 in

Width

Spare room +3.2 in

Bag 12.5 in / Rule 15.7 in

Depth

Spare room +2.9 in

Bag 5 in / Rule 7.9 in

  • warning: This result uses medium-confidence source data.

Data status

Audited dimensionsSource-linked rule

Rendered from the dimensions shown here. Airline staff and packed shape can still affect the real-world outcome.

Dimension-only silhouette rendered from verified dimensions; no approved product image is available yet.

Bag
17 x 12.5 x 5 in
Rule
21.7 x 15.7 x 7.9 in
Risk
8/100
Confidence
medium

Margins: length 4.7 in, width 3.2 in, depth 2.9 in.

Personal item

Knack Bags Series 2 Small Expandable Backpack

Does not fit

Knack Bags Series 2 Small Expandable Backpack is larger than the published personal-item dimensions. Pick a smaller alternative for this airline rule.

Bag
17 x 12.5 x 5 in
Rule
13 x 9.8 x 7.9 in
Risk
92/100
Confidence
medium

Margins: length -4 in, width -2.7 in, depth 2.9 in.

Main issue: length by 4.0 in, width by 2.7 in.

Carry-on

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag
17 x 12.5 x 5 in
Rule
21.7 x 13.8 x 9.8 in
Risk
8/100
Confidence
medium

Margins: length 4.7 in, width 1.3 in, depth 4.8 in.

Personal item

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published personal-item dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag
17 x 12.5 x 5 in
Rule
17.7 x 13.8 x 7.9 in
Risk
8/100
Confidence
medium

Margins: length 0.7 in, width 1.3 in, depth 2.9 in.

Carry-on

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag
17 x 12.5 x 5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium

Margins: length 4.7 in, width 3.2 in, depth 4.1 in.

Carry-on

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag
17 x 12.5 x 5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium

Margins: length 4.7 in, width 3.2 in, depth 4.1 in.

Carry-on

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag
17 x 12.5 x 5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium

Margins: length 4.7 in, width 3.2 in, depth 4.1 in.

Carry-on

Knack Bags Series 2 Small Expandable Backpack

Fits

Knack Bags Series 2 Small Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.

Bag
17 x 12.5 x 5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium

Margins: length 4.7 in, width 3.2 in, depth 4.1 in.