Grimloc Carabiners
Grimlocs are plastic carabiners shaped as a "D". They are commonly used to attach puches or not very heavy equipment to packs.
The design minimizes IR emission so they are stealth to night vision equipment. To open just press the top button to close press firmly.
They can be used with gloves and don't get stuck with sand or dirt. I found these particularly useful with Maxpedition packs for attachment points.
Available in Tan, Black and Green.
You can get them in Packs of 4 for $8 from Tad Gear and other good suppliers.