These days, I make knitting needles by cutting steel music wire to length, grinding the ends flat or slightly domed, and polishing the burrs off the edge. Pix of the needles I have been using (in the Redwoods).
Needles in the range of 2 - 2.4 mm. The cross section of the ends is round.
The 2 knitting sheaths that went with me to the Redwoods.
A worn and machine washed (in hot water) "swatch". (This yarn is NOT labeled as washable!!) The yarn is a 3x2 cabled yarn that I am using for all my hiking socks this year. RIW got 12" high socks of this design/yarn and used them for a dozen days of skiing last winter. He tells me that they work as well as the Shetland yarns I had been using for his ski socks.
A swatch as it comes off the needles - these anklets I wear on the Nordic track. I like the pointed toe to cushion my toes.
The belt I wore over my swimming trunks to hold my knitting sheath. (It came with some cheap shorts from Costco.) It does not work very well for pointed needles with a knitting sheath - (they need more support, e.g., a leather belt), but it works well enough with flat ended needles. Flat tipped needles really do simplify the whole knitting sheath concept.
I do not suggest that flat tipped needles work very well for hand hand knitting. Ball tipped needles work OK hand knitting soft woolen fabrics, but pointy really is better for hand held knitting.