I have two types in both my kits. One is the Lektra Swiss Army button compass as found in the Victorinox Swisschamp Survival kit etc. and the other is a Silva button compass on a zipper pull. Both are very accurate. I have had the SAK Button Compass for about 8 years now. The Silva, I have had for about a year. Both have been checked against my Eschenbach Marching Compass of about 14 years and my Konustar, which is a recent acquisition. They have also been compared to my digital compass on my Casio Wademan G-Shock. They are all within a degree or so. Hope this helps. Oh, the Silva button compass is dirt cheap, about 2 US Dollars equivalent. The SAK button compass about 3 US Dollars equivalent.