Sling bag?
He got it nowhere! : P
I think it IS OKAY
A haversack is different from a backpack in many ways. For example, a haversack only has one strap to hold the bag on one's shoulder, while a backpack has two.
The possessive form for the singular noun backpack is backpack's.Example: My backpack's strap is broken.
The possessive form is backpack's. Example sentence:My backpack's shoulder strap is broken.
The possessive form for the singular noun backpack is backpack's.Example: My backpack's strap is broken.
To prevent backpack bouncing while running, you can adjust the straps to fit snugly on your shoulders and chest, use a backpack with a waist strap for added stability, and pack your backpack with heavier items closer to your back.
A rucksack or (backpack, haversack, knapsack, packsack) is a bag carried by a strap on your back or shoulder.
Strap length. Distance from backpack center-of-mass to center-of-tread.
A waistbelt is a belt or strap worn around the waist, especially as part of a larger article such as a backpack.
It depends on what you want to measure: its length. width, thickness, strength, elasticity, resistance to abrasion. Since you have not bothered to provide that crucial bit of information, I cannot provide a more useful answer.
For a backpack baby carrier to be considered safe it should have strap on hip carriers with slings. It should also be certified and comply with guidelines by the "JPMA".