Astro Pneumatic 5-3/4” Extension Nose Piece 1426 Astro Pneumatic 1/4” Heavy Duty Hand Riveter 1426FNP The Astro Pneumatic 5-3/4” Extension Nose Piece 1426 Astro Pneumatic 1/4” Heavy Duty Hand Riveter 1426FNP unit allows the nose piece of the 1426 1/4” Astro Pneumatic Heavy Duty Hand Riveter to be extended to 5-3/4”. Unit can be interchanged quickly and easily.