Scrabble Boosters (Scrabblers) are unique lasercut bigram and trigram tiles that form words. Play various new word games or enhance any Scrabble™ game. These double and triple letter tiles give you extra points for extra fun!
There are currently at least six ways to use Scrabblers tiles:
Gridlock mode
Flip mode
Stackers mode
Solitaire mode
Boardless Crossword mode
Scrabble addon expansion
—description from the publisher