Size: the diameter of thread part is approx. 0.78 inch, length of thread part is approx. 0.62 inch; Style A and Style B are the same size; please check the size of the inflatable boat valve before buying. Compatibility: this standard Boston valve replacement set fits most kayaks, inflatable boats, rafts, rubber dinghies, and similar inflatables; not universal, so measure your valve size prior to purchase. Note: measure your existing valve size before ordering; Style A and Style B are identical in dimensions; this kit in Style B includes the same components as Style A but without the gasket; all 8 pieces are the same size. Material: made of high-quality dense ABS plastic, offering durability, strength, and resistance to corrosion. Design: features a secure valve cap to help prevent air leaks; two-way air valve design allows for quick and easy inflation and deflation.