LATERAL MASS SCREWS set of 12 POLYXIAL SCREW 3. 5 MM/ 4. 00 MM EXCHANGABLE WITH LOCKING CAP/ INNER with connecting rod Titanium. Specification- 3. 5/ 4. 0 mm exchangeable with locking cap/ inne compatible with 5. 5 rod Should be compatible with cervico dorsal fixation both open, minimally invasive and navigation Take of titanium Should be in sizes 3. 0, 3. 5. 4. 0 mm.