Buy 2 Gillette Mach 3 Razor @ $9.99/ea = $19.98 (sale price)

Use two $2/1 Gillette Razor (P&G 10/25, x11/21) = -$4

Pay: $15.98

Get Back: $8 ExtraBucks for buying 2 (limit 1)

Final Price: $3.99 each or $7.98 for both