Rob Smith's Silicone Flow No Bead Blood Arterial - Venous - Aged 150ml Robert Smith Blood £4.80 Out of stock. Silicone Flow Blood is mouth safe and washable but has extra flow properties. It will run like real blood and not bead on silicone props/appliances and direct applied effects. Available in 3 shades Artierial ( Light) Venous (Dark) Aged Silicone Flow Blood is Sorbitol based and was developed to flow naturally on silicone props. It is very free flowing on skin and smudges very thinly.