Super Glue holds structures in Contraptions together, like Slimeballs. The main difference between Super Glue and Slimeballs is that Super Glue does not need to use the wooden face of a Linear Chassis block to adhere blocks to each other. Super Glue has 99 durability and is not one-time use, unlike Slimeballs. (may disappear from structures this is a glitch in 1.16.5)
|Super Glue||Slimeball +
Iron Nugget +
Blocks can be automatically glued onto a structure by having Super Glue in the off hand. Otherwise, right clicking a block with Super Glue applies it to that face of the block.
Once a piece of Super Glue is connecting two blocks together, that piece of Super Glue will only be visible while holding Super Glue.
Super Glue has durability, meaning that it can be used many times before being fully used up. Super Glue can be enchanted with Unbreaking and Mending to extend its life.