Add to Cart SALE MidNite Solar MidNite Solar MNHYDROMETER Battery Hydrometer $50.00 $40.99 MidNite Solar MNHYDROMETER Battery Hydrometer. Easy to use battery hydrometer for checking the specific gravity on all "Flooded" style batteries. Size 5.25"L x 4.25"W x 1.5"D FAQ Can the MidNite Solar MNHYDROMETER be calibrated? No. Since this is a... Compare Add to Cart Add to Wishlist