Reduced: Nikon PK-13 27.5mm AI extension tube and caps | Location: MD, US | Ships: US Buy & Sell Listing - Want to SellSelling</br> Nikon PK-13 27.5mm AI extension tube for macro close focus </br>Prices</br> PK-13 $39.95 </br>Location</br> MD, US </br>Ships to</br> US </br>Description</br> The PK-13 extension tube permits closer focusing with Nikon AI lenses. Its 27.5mm length will double the magnification of Nikon's 55mm macro (Micro-Nikkor) lenses. The PK-13 allows closer focusing and greater magnification with other AI lenses, too, but macro lenses are designed for the closest focus and highest magnification. The PK-13 is for AI and AI-compatible lenses and cameras. Non-AI lenses will not fit on it. The device mechanically communicates aperture with the camera. The lens must be focused manually, which generally isn't a problem because macro shots are usually focused manually anyway. This tube works by extending the lens's focal length. It has no glass so it does not compromise the optical quality of the attached lens. The PK-13 is a simple but useful and well-engineered product, still sold by Nikon. This particular tube shows signs of wear on close examination, but it is mechanically sound and takes close-up photos as well as it did when it was brand new. Front and rear caps (not pictured) are included to prevent dust from accumulating and to protect lens mounting surfaces. </br>Payment accepted</br> Regular PayPal (fee included in price) Shipping method</br> USPS Priority to PayPal-verified US address </br>Shipping charge</br> FREE </br>Handling time</br> 1 business day </br>References</br> Ebay: biffl </br>Additional comments</br> Will ship only to the address on the PayPal transaction details page Acknowledgement</br> I have read and agree to the Buy and Sell rules.