New Balance has announced a new running shoe model that incorporates a 3D-printed midsole. The shoe will be available in April in Boston as a limited edition collection, with the release timed to coincide with the Boston Marathon. New Balance will sell “a couple hundred” of them in 2016 and intends to expand its retail operations to more global metropolitan locations thereafter.

The design is an update to New Balance’s Fresh Foam Zante model. However, instead of gluing a traditional foam midsole into the shoe, the new shoe will incorporate a 3D-printed midsole. Shoe brands are competing to achieve a lighter, more quickly made shoe, and they are using 3D printing to do it.