Kwila is a medium-priced South East Asian tropical hardwood from a sustainable and renewable source. It is popular in New Zealand for decking due to its relative ease of installation, excellent lifespan and low maintenance requirements. It also provides a high-end premium finish. It starts as an attractive red/brown colour, and then ages to grey when left to weather. There is a danger that it will bleed tannins when it is first laid, so you will need to be mindful of this.