This is a quick and easy pattern for a hot water bottle cover. It is knit in the round with a simple cable pattern on each side. The pattern is designed for a standard sized hot water bottle, but tips are given for adapting the pattern if yours is a different size.
When substituting yarn, animal fibres such as wool, alpaca and cashmere are a good choice because they are excellent insulators and will help to keep your hot water bottle warmer for longer.