● Powered by ecoflex® BMB: CircleCELL™ is the first footwear application of BASF’s biomass-balanced biopolymer, ecoflex® BMB, supporting the footwear industry to increase the use of renewable feedstock to produce a durable, high-rebound foam.
● Performance Without Compromise: CircleCELL™ provides energy return on par with industry-standard PEBA while offering nearly double the running lifespan, solving the traditional trade-off between sustainability and durability.
Düsseldorf, GERMANY – September 30, 2025 – The ultrarunning footwear specialist Mount to Coast now commercially launches the H1, the first running shoe featuring CircleCELL™, a revolutionary midsole technology using renewable feedstock. This innovation, powered by BASF’s biomass balanced biopolymer ecoflex® BMB, will be displayed at the BASF booth at K 2025, the world's largest trade fair for the plastics and rubber industry, taking place from October 8-15 in Düsseldorf, Germany.
CircleCELL™ directly addresses the growing demand within performance sports for materials that minimize environmental impact without sacrificing elite performance. It is the first high-performance midsole material manufactured from seven kilograms of renewable feedstock via biomass balance approach per pair. In ecoflex® BMB, fossil raw materials are replaced with renewable feedstock at the beginning of the production process. The renewable feedstock comes from organic waste and residual biomass and is attributed to the ecoflex® grade via a mass balance approach which is certified according to REDcert2 and ISCC PLUS (1). The result is a high-rebound, durable foam created through an advanced foaming process.
In extensive testing, CircleCELL™ delivers energy return comparable to the highest-performing PEBA foams, while crucially offering almost double the material’s typical running lifespan. This breakthrough in durability proves that sustainable materials can meet and exceed the rigorous demands of elite endurance athletes.
“The Mount to Coast H1 is tangible proof that our biomass balance approach allows partners to develop category-defining products that drive the circular economy forward,” said Marcel Philipp Barth, head of global business management Biopolymers at BASF, “Ecoflex® BMB perfectly fits into BASF’s pioneering footwear solutions and deep expertise of the entire value chain. With this biopolymer, we are demonstrating that sustainability and high performance can combine without compromise, and we invite fellow footwear industry leaders to explore this next-generation foam with us in Düsseldorf.”
The Mount to Coast H1 with CircleCELL™ technology has already been validated at the highest level of sport. In January 2025, elite ultrarunner Jamil Coury logged over 600 miles (965 km) on a single pair of H1s while winning a 730-mile endurance challenge, validating the material’s exceptional durability and performance under competitive stress.
“Everyday runners should not have to decide between performance and sustainability,” says Yeti Zhang, Mount to Coast’s head of product. “Our goal is to innovate at the frontier of sustainable material science and endurance goals without compromising the most important needs of ultra runners – durability, energy return and comfort. BASF has been an indispensable partner, providing the material expertise to help us solve the sustainability-durability paradox. We are excited to now be able to invite trail runners into our community and offer the most durable shoe with a clear sustainability advantage on the market in 2025.”
Visit BASF from October 8-15 at K 2025 in Düsseldorf, Hall 5, Booth C21/D21, to see the Mount to Coast H1 midsole and learn more about ecoflex® BMB.
Further information:
mounttocoast.com
www.ecoflex.basf.com/bmb
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About Mount to Coast™
Mount to Coast is a technical footwear brand specializing in long-distance running and biomechanics research to challenge the limits of ultrarunning. Founded for athletes who transcend distance, Mount to Coast integrates innovative materials inspired by various industries to engineer footwear offering exceptional comfort, support, energy return and durability. Its first four models – R1, S1, P1 and T1 – crafted with insights from Mount to Coast’s Run Research Lab, are award winning, record-breaking shoes, vigorously tested in highly challenging races and evaluated by elite athletes.
(1) REDcert² and ISCC PLUS are sustainability certification schemes for the use of sustainable biomass as raw material in the chemical industry. A certification according to these certification schemes confirms that the biomass used is sustainable and has been fed into the production system in the required amount. It also confirms that the sustainable biomass has been correctly attributed to the corresponding sales products. The certifications are awarded on the basis of on-site audits conducted by independent auditors.
Media Contacts:
Mount to Coast
BASF
Ulla Biernat: ulla.biernat@basf.com