From SpongePedia, the First SpongeBob Wiki.
Ol Reliable in Nature Pants
Ol Reliable in The Pink Purloiner
Ol' Reliable is SpongeBob's faithful Jellyfishing net. It has only appeared in 3 episodes.
In the episode Nature Pants it was just shiny gold and in The Pink Purloiner and Best Day Ever it was blue and silver with many other features installed.
In the episode The Pink Purloiner, SpongeBob loses Ol' Reliable and thinks Patrick has stolen it. Later it turns out that SpongeBob just forgot it in the bus.