The Bellows Set for UMB-1 Universal Matte Box from Wooden Camera includes a 143mm diameter matte box bellows ring with 138mm round polarizer slot, rubber bellows, and a 114mm standard opening. The complete set of reduction rings included snap into the bellows quickly, making lens transitions fast and easy. These reduction rings are compatible with 3rd-party 114mm threaded bellows via their specially designed tabs.
Wooden Camera 202500 Specs
143 mm rubber bellows with 138 mm round filter slot