Boat lift tackle - BL003 - Blocks with cam cleat and 5/16" rope included - Ready to use

Boat lift tackle
BL003 -SET OF BLOCKS WITH ROPE AND SNAP SHACKLE . 
4:1 PURCHASE.
SET INCLUDES
2 DOUBLE FIXED WITH BECKET BALL BEARING 39 MM SHEAVE BLOCK
2  DOUBLE FIXED WITH CAM AND BECKET BALL BEARING 39 MM BLOCK
2 SNAP SHACKLES
92 ft PRE-STRECHET ROPE - 5/16" - POLYESTER DOUBLE BRAID  ROPE- IN TWO SECTIONS (46 ft EA.)
WORKING LOAD ( EACH LINE) 600 LBS
BREAKING LOAD ( EACH LINE) 2000 LbsROPE COLOR MAY VARY

often working in pairs, used on BOATS or buildings to lift and lower heavy items like boats, anchors, cargo.
Davit tackles are pulley systems used with davits (crane-like arms) on boats or for industrial safety to provide mechanical advantage for lifting and lowering heavy objects, like dinghies, lifeboats, , making tasks easier with reduced effort through multiple pulleys. They often feature a block and tackle setup with multiple sheaves (pulleys) and rope, sometimes with cam cleats for securing lines. 

• By routing the line through multiple pulleys, the effort needed to lift a load is significantly reduced (e.g., a 4:1 system requires one-fourth the force).