This is an older run of pink barstamp ESP Zones from Discraft. They are especially tacky and flat with a relatively low profile as far as zones go. These are great for throwing putters that will break in over-time.
Here is what Discraft says about the Zone: "Advanced players love the overstable, low-profiled Zone putter. Will hold the line without flipping on long approaches, and delivers predictable putts even in windy conditions."