Sanford Ink Corporation Products - Uniball Gel Impact Refill, Bold Point, 2/PK, Black Ink - Sold as 1 PK - Refill for Sanford Uni-balls Gel Impact provides an ultra smooth ink flow. The 1.0mm refill features acid-free, water-resistant and fade-resistant ink for thick, vibrant writing. Manufacturer: Sanford Ink Corporation - Products