The Lethal 70 has a hollow shaft with a newly designed T-Joint from Apac. In it's torsion test, it was twisted up to 4 degrees. The racket's stable frame allows for a max tension of 45lbs. Specification: Frame Material: 30T HM Graphite ( Mitsubishi M30 ) + Titanium Mesh Shaft Material: 40T HM Graphite ( Toray M40) Flex: Stiff Shaft Dia.: 7.6 mm Weight: 3U (86-89g) G2 Length: 675mm Max Tension: 45lbs Balance: 290 � 3mm (Head Heavy) Special Features: -ISO frame -Full Titanium Mesh Power Frame -Multi-layer Linear Fiber construction shaft. -Ultra Low Twisting angle on Tosion test.