Blackriver's Pocket Quarter was an on-the-go fingerboarder's dream, but size matters at some point. The Pocket Quarter XL is wider than the original so you have more options, but you keep that small form factor for easy transportation. Quarters are a must have if your fingerboard park lacks smooth transition from one end to the other, and the Pocket Quarter XL is even better for the more compact desk setups.
The Diamond Coping is Blackriver's latest development; it produces a satisfying sound but is still silky smooth to grind.