-Plastic Shaker Bottle.
-Generally cheaper than Stainless Steel.
-Be sure to only use BPA-Free bottles
(should also be free of Phthalates, BPS, and Tritan).
-Be sure to never put any plastic in the dishwasher (even on the top rack) due to the leaching of toxic hormone-disrupting chemicals.
-Use a convenient Bottle Brush to hand-wash Plastic Shaker Bottles.