Free Sample of Wisk Detergent and $1 off Coupon May 20, 2011March 9, 2011 by Steph Post contains sponsored/affiliate links and I get commissions for purchases made from links. This is available again if you missed it. Go here to request a sample of Wisk detergent. The $1 off coupon will only be valid at CVS according to the website. Your sample will arrive in 4-6 weeks.