Small wing for small cylinders, where to buy?

[happy-diver]

Dude!
Increase the length of your stitches, adjust the thread tension, and feed the tarpaulin along the edge of the foot

 

[SelfDiver]

Pimped China Wing, Seac inflator (less bulky), pull dump valve, shorter corrugated hose, black tarpaulin including holes for STA, no handle and protection.

Good job!
You made a BCD!
The stitching looks kind of wonky but the picture is not that clear.
What kind of sewing machine are you using?
The stitch length looks too short for the black plastic fabric and creates a weaker connection due to perforation. (For example: vinyl coated fabrics recommend 3-4 mm length)
You should use an edge guide foot or a blind hem foot or some kind of foot that allows you to line up the stitching to the outline.
I can't tell from the picture, but is the thread fuzzy? This can be from incorrect needle for the fabric/thread. It an sometimes just be a degraded/low quality thread or the machine needs a cleaning.

 

[Agro]

Stitching is perfectly OK, no worries.

Machine is a Pfaff 360.

Plastic fabric has a lot of textile in there, short stitches are OK.

Thread is fine as well.