Because the hammocks is close to indestructible a wearout could arise over the lifetime. This could be caused especially by weather. It can not be excluded that customers hang their hammocks unprotected outdoors all year long. We use the wood of Douglas fir. The Douglas fir is an evergreen coniferous tree with softwood. It has a reddish to brownish grain. The wood is very durable, weather-resistant and virtually free of knots. The heartwood is according to DIN 68364 (1979) in resistance class 3 („moderately durable“) classified and can therefore also be used in areas without chemical preservatives, where an occasional wetting can not be excluded (hazard class 2). In addition the wood of Douglas fir is not resinating. A rusting of the ropes seems impossible, because we only use galvanized or stainless steels.