I have 2 Volkl Catapult v10 V-engines in 4 1/2. Both are strung with Technifibre X-1 Biphase (Red) @ 55#. One has been used for 2 1.5hr tennis lesson and the other has been used for 1 lesson. Both had overgrips installed. $80 each or $150 for both. Please email me @ email@example.com.