Stand-up bases allow a wide variety of blocks to be held upright, swivel freely, or pivot so lines have a fair lead under load. Use the Midrange/Cruising ESP Stand-Up Base with Midrange blocks and 57mm or 75mm Cruising ESP blocks. The low-profile design is ideal for mast base and halyard lead blocks. Stand-Up Boots are made of durable, flexible PVC, and they hold blocks up without snagging lines. Springs support blocks on padeyes, eyestraps, bases, and traveler cars, and they prevent blocks from hitting the deck. The U-Adaptor shown below allows blocks with 3/8" (10mm) posts to be attached to swivel bases or to other blocks with 3/8" (10mm) posts.
