T-H Marine Z-Launch Boat Launch Cord The T-H Marine Z-Launch Watercraft Launch Cord makes solo watercraft launching easier than ever. This launch cord is made of premium elastics and uses automatically adjusting tension when you back your boat, jet ski, or tow rube into the water, so it wont jerk your watercraft around when you pull the trailer forward. Expandable to more than 20. Simple and safe operation No-hassle design Attaches easily Expands to more than 20 Unlike rope, will not jerk your w