My version of the seatbelt sling.  Using 2” wide backpack nylon webbing for the pouch, nylon mason line for the whipping at pouch ends, and 550 paracord for the rest.

I like to tie two stopper knots 0.5” apart on the release cord to bracket the top of my index finger.  I also use as scaffold knot for the retention loop so I can snug up the loop tight on my middle finger.

So far made a 19” version for inside the house, a 29.25” as my standard length, and a 39.25” for my long range, underhand (any longer and it will hit the ground).  Pic is of the standard length.