Buy (4) Purex Crystals, 20 lds for $5.49

Buy 1 Purex Crystals Get 1 Free 

Use this Printable Coupon 

-B2G1 Free Purex Crystals In Wash Fragrance Booster (Max value $3.99)

Final price is $6.99 – $1.74 each, WYB 4

Notes 

The coupon only pays up to $3.99 maximum so $1.50 was added to the above final price.