The Spin Lab is a great slot from NYX Gaming.
It features an Atomic Scatter symbol which is multiplied by the bet to give you much bigger wins (5 Scatters multiplies the win by 625!) The Wild symbol substitutes for all symbols and can multiply your bet up to a massive 1000 times.
But the best feature of the game is The Spin Lab itself. Get 3, 4 or 5 Scatters and you enter the Spin Lab for 5 free games, during which you get to customize your options - you get to choose one element to change for each of the three categories ie symbols, wilds and paylines.
This free game is provided by Guts casino. They give you 1,000 play money credits to play for as long as you like!
Sign up at Guts casino and get a €300 bonus, plus 100 free spins on Starburst!
Check out the casinos below for the best free Slots bonuses currently available.