e-breathe filter A1B2E2K1 fits the e-breathe e-flow - PAPR motorized respirator. The eco-friendly filter is made from recycled materials. The filter is sealed with a special rubber coating specifically developed for the turbo unit. Extremely easy to install. To mount this A1B2E2K1 filter, an adapter (e-breathe adapter for gas filters) must be purchased. Note: Two A1B2E2K1 filters and two adapters are required per motor unit.