Prevent your blocks from laying down on the job. These boots and springs keep blocks upright which improves the lead angle. Use the boots where snagging could be a problem or in combination with a spring for heavy blocks.
Spring Cup (HSB2) keeps blocks seated in the upright position for better lead angles and can be used with any swivel post block and an H071 spring. The tapered springs should be used only for loop top blocks, the non-tapered can be used for loop top or swivel post blocks.