North Castle Partners, a consumer-focused private equity firm, has invested growth capital in Ignite USA, maker of reusable, environmentally friendly thermal mugs and hydration bottles. Through its Contigo and Avex brands, Ignite sells travel mugs, water bottles and kids cups in more than 50 countries and across a variety of partnerships. North Castle will leverage its experience in consumer products, mass-market distribution and channel expansion to help grow the company. The firm focuses its investments in consumer-driven products and services that promote healthy, active lifestyles.