Mono Base Topper – 2” x 4"White Collection (2 x 4 Base). The Mono Base Topper (2 x 4) from our White Collection is made for women with mild to moderate hair thinning, especially in the front scalp area. This topper provides wider, natural looking coverage while staying comfortable, lightweight, and perfect for everyday wear. It is ideal for clients who want more coverage than a small base topper but do not need a full wig. Who This Topper Is For This topper is designed for