Even after filling all the filler bags, I can only get 75% of the advertised weight of the workout sandbag. Why?
There are a number of different types of sand. Play sand is common but is not particularly dense. Zircon is the heaviest type of sand, followed by Chromite. Zircon is 98% heavier than Play Sand, while the black Chromite sand is 94% heavier than Play Sand. Riverbed Sand, commonly sold in pet stores as “Reptile Sand”, is less dense, measuring about 55% heavier than Play Sand. There are around $3 bags of sand you can buy at Home Depot that will easily get you over 50 lbs (for medium workout sandbag) and 120 lbs (for large workout sandbag).
Can I buy additional filler bags?
Certainly. You can buy additional filler bags for medium workout sandbag here, and filler bags for large workout sandbag here.
How do I register my sandbag for warranty?
You can register your workout sandbag here.