very rare and seldom found 19th century commercial studio varnished oak wood mobile h-frame easel. attributed to the specialty woodworking co., philadelphia, pa. the large fully adjustable and/or collapsible industrial easel is rather complex in design with vertical posts, horizontal cross bar supports, masts and a centrally located segmented or notched track allowing for the easel's verticality to be adjusted. the overall design of the easel is generally based on right angles with all posts being parallel to each other with the base of the easel being rectangular. the original swivel caster wheels remain in working condition. measures 88 x 30 x 27 inches (taken from the configuration as depicted in the photograph above).