17-4 stainless steel, certified, aircraft grade, condition A, center-less ground to ensure absolute straightness, rust resistence, and consistency. Manufactured in a state of the art machine shop with CNC mills, lathes, drilling centers, and straightening machines. In house, digitally controlled, heat treating oven. All machines and materials are made in the USA. All machining is done on site, under strict quality control methods, to ensure the finest spear shafts available. 
 
Custom shark fin tab height and spacing configuration make these shafts ideal for use with double roller spearguns using a bridged muzzle. 5cm tang length with euro notch. 3/32" shooting line hole drilled through the 2nd tab forward, as not to impede the stacking of wishbones. Both wishbones can be stacked on the rearmost tab.
 
{Remember to load the wishbone from the smaller roller wheel to the rearmost tab, and the larger roller wishbone to the 2nd tab forward or stack it on the rearmost tab, to avoid the possibility of a muzzle wrap.}
 
Standard 5/32"-24 thread pitch for attachment of most 8mm/5/32" slip tip bases on the market.  
To get an ideal 7 1/4" shaft overhang with a  mounted slip tip, select a shaft length that gives you a 4-5cm overhang. Always consider the trigger take up, actual barrel length, and muzzle length, when calculating the overall length. 
 
For example: if you're using an Ermes Avatar handle with a reverse roller trigger mechanism (12cm trigger take up), a 110cm carbon fiber barrel, and a Manny Sub double roller muzzle (14cm), you will have an overall length of 12+110+14=136cm. If you select the 140cm shaft length, you will have a 4cm overhang. That will leave just enough room for the slide ring to sit a half inch forward of the muzzle once the slip tip has been installed. Perfect!