Buffered Vitamin C Powder is available by Designs for Heatlh.

Buffered vitamin C is created by linking ascorbic acid with a mineral such as calcium, magnesium, and potassium. This form of vitamin C is non-acidic, which means it is much better absorbed and provides the additional benefits of calcium, magnesium, and potassium supplementation. The body does not make vitamin C, so it must be taken in through diet. Benefits of Vitamin C supplementation include immune system support, adrenal function, collagen formation for healthy skin, and cardiovascular health.

Ingredients:

Dosage:
As a dietary supplement, take 1/2 teaspoon (3 grams) per day or as directed by your health care practitioner.

WARNINGS:
STORE IN A COOL, DRY PLACE. KEEP OUT OF REACH OF CHILDREN.