Good dimension-variant test case. | Official Knack page shows 24L unexpanded, 35L expanded, 19 x 12 x 4.5 in, and 3 lb. | Launch-only softness, compressibility, opening, bottle-pocket, and price fields inferred from category and model.
Knack Bags Series 2 Medium 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: 2.7 in.
Dimension-only silhouette
Fits. Tightest spare room: 2.7 in.
Height
Spare room +2.7 in
Bag 19 in / Rule 21.7 in
Width
Spare room +3.7 in
Bag 12 in / Rule 15.7 in
Depth
Spare room +3.4 in
Bag 4.5 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
19 x 12 x 4.5 in
Rule
21.7 x 15.7 x 7.9 in
Risk
8/100
Confidence
medium
Margins: length 2.7 in, width 3.7 in, depth 3.4 in.
Knack Bags Series 2 Medium Expandable Backpack is larger than the published personal-item dimensions. Pick a smaller alternative for this airline rule.
Bag
19 x 12 x 4.5 in
Rule
13 x 9.8 x 7.9 in
Risk
92/100
Confidence
medium
Margins: length -6 in, width -2.2 in, depth 3.4 in.
Knack Bags Series 2 Medium Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.
Bag
19 x 12 x 4.5 in
Rule
21.7 x 13.8 x 9.8 in
Risk
8/100
Confidence
medium
Margins: length 2.7 in, width 1.8 in, depth 5.3 in.
Knack Bags Series 2 Medium Expandable Backpack is larger than the published personal-item dimensions. Pick a smaller alternative for this airline rule.
Bag
19 x 12 x 4.5 in
Rule
17.7 x 13.8 x 7.9 in
Risk
78/100
Confidence
medium
Margins: length -1.3 in, width 1.8 in, depth 3.4 in.
Knack Bags Series 2 Medium Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.
Bag
19 x 12 x 4.5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium
Margins: length 2.7 in, width 3.7 in, depth 4.6 in.
Knack Bags Series 2 Medium Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.
Bag
19 x 12 x 4.5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium
Margins: length 2.7 in, width 3.7 in, depth 4.6 in.
Knack Bags Series 2 Medium Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.
Bag
19 x 12 x 4.5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium
Margins: length 2.7 in, width 3.7 in, depth 4.6 in.
Knack Bags Series 2 Medium Expandable Backpack fits the published carry-on dimensions for this rule. Still measure the packed bag, including handles and wheels.
Bag
19 x 12 x 4.5 in
Rule
21.7 x 15.7 x 9.1 in
Risk
8/100
Confidence
medium
Margins: length 2.7 in, width 3.7 in, depth 4.6 in.