Based on 4 r/BuyItForLife mentions

Convertible Hand Truck

$352.99

Magliner

Combination hand truck as 2 or 4 wheel transport Easy release bar to convert usage Aluminum construction is lighter weight and rust proof This hand truck can be used on 2 wheels or converted to a 4 wheel platform transport. The platform will handle a weight load of 1000 lb. This hand truck on 2 wheels will hold up to 500 lb capacity. Conversion of this transport is handled by the press of a release bar.

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Product details
Load Capacity
500 lbs (hand truck)
Weight Capacity
500 lbs (hand truck)
Material
Aluminum
Product Type
Hand truck
Color
Silver
Use
Transport
Depth
7-1/2 in (noseplate)
Height
61"
Length
51 in (platform)
Width
21 in
Size
Senior
Weight
52 lb
Wheel Count
2
Wheel Type
Pneumatic
Assembly Required
Yes
Durability
All parts are replaceable
Highlighted Features
Modular design
Handle Type
Dual
Top Use Cases
Any surface
Compatible With
All Surface Types
Configuration Type
Hand Truck
Item Count
1
Configuration Subtype
Convertible Hand Truck
Design Style
Open Nose Plate