These iconic helmet nets were issued to East German troops from the 1960s through the end of the Cold War. Made of durable polyester, these have hooks that secure the net to the rim for a nice snug fit. These are great on size 1 and 2 shells, but some elbow grease is required to stretch them over a size 3 shell. It's not impossible, just a bit more work.
These are all unissued, and come with different packaging, or none at all as pictured in the second photo. LISTING IS FOR ONLY ONE NET. Helmet NOT included, the picture is just to show what they look like secured to a helmet.