Pressure treated spruce sleepers 1.8m x 0.2m x 0.1m. These boards are used for making more chunky raised beds or for creating retaining garden walls. The pressure treated timber will have a life of 10-15 years but can be longer if treated with a wood oil. If using these Sleepers for producing your own food it is advisable to use a liner so that the wood treatment doesn't leech in to the soil and your plants. This is not an issue when growing ordinary garden plants.