300 Standard Vise Base Panavise Vice All Vise Heads are compatible with the 300 Standard Base, the 305 Low Profile Base, and the 380 Vacuum Base. A new or additional head will add extra productivity to your existing PanaVise, or start here to build your own work holding solution! All stems are 5/8" (15.9mm) in diameter. * Model: 300 Standard Base * Our most popular base! * Holds all regular PANAVISE heads and Circuit Board Holders. * The patented load control knob and the exclusive split-ball feature have a range of tensions which permits moving of work to any position desired. * In addition, loosening of this knob reduces the load on the split-ball permitting the head to be removed from the base. This unique feature permits you to get multi-use from the one base. * Accepts all 300 series Heads and the PV Jr. 203 Head or any 5/8" (15.9mm) diameter shaft. Create a versatile work-holding system by selecting two or three different Heads! * Single control knob and exclusive "split-ball" locks the head firmly in place * The base features 4.3125" (109.5mm) bolt circle countersunk for three 1/4" (6.3mm) flat-head screws (not included) * Height: 3.75" (95.2mm), Weight: 1.4 lbs. (0.6kg)