Adjustable Protein Skimmer Stands. Designed specifically to fit the authentic Bullet Series, these trick stands will also provide additional space in your stand above a water pump for storage, etc. Specifications: Model: SL1 Overall Dimensions: 9” x 5.5” Minimum Height: 3 .125” Maximum Height: 5.25” Model: SL2 Overall Dimensions: 10” x 6.5” Minimum Height: 4 .125” Maximum Height: 7.25”