This replacement raw steel weld on center spring hanger is perfect for boat trailers or enclosed trailers using 9/16 inch leaf spring bolts. The hanger is used on tandem axle trailers, so you can attach your equalizer bar in the center of your spring setup. The equalizer bars that are used with this hanger measure approximately 1 ¾ inch wide. The hole size is for a 9/16 inch diameter spring bolt. The dimensions of this hanger are 3 inch long and 4 1/4 inch tall, with an inside measurement of 1 7/8 inch.