This is a very nice, clean single rope pulley marked "H-25?" on one of the inner cast iron spokes of the pulley wheel.  Top quality, believed to have been made by Starline.  This one has a nice spoke wheel and sort of cast cut-out design.  Originally produced in the 1910's to 40's era.  The all metal design of mostly cast iron made this design very strong and durable.  The rope carrier is 4" wheel that has a steel bushing, with a steel rivet at the center.  The cast iron pulley wheel is in good useable condition with smooth movement a little wear, no damage.  At the top of the assembly is the double action swivel which has a steel nut and bolt to hold it in place.  Works great.  From the top of the swivel link to the bottom of the pulley is 9.5".  There is no rust evident on the steel, only minor amount of silver paint intact.  The surface has been treated with vegetable oil to prevent rust, (can be easily washed off if you wish to paint).  Overall a nicely formed barn/farm use type rope pulley!