Have used them for years, wonderful for decalcifying bone samples, then
doing xray endpoint checks, with bone in bag, and often, using the bags
to hold large bones, or whole rat femurs/knees/tibias, a one shot handling
system.  

Also use them to hold silica gel inside black plastic slide boxes to 
maintain frozen sections in dry environment after coming out of freezer and
warming up to RT.  

The price was always worth the versatility of usage.  We keep all three sizes
on hand.

Gayle Callis