Mirrorless / SLR / Extension Rings / Sea & Sea Extension Ring 40L CloseSea & Sea Extension Ring 40L Zoom Sea & Sea NX Extension Ring 40L with Port Lock SKU: # ss-30125 FREE Standard Shipping to USA / Canada! Price $299.95 Options Back Item IncomeAccount TaxCode Mapping UDF1 UDF2 UPC Code Pick Up Tax Amount Quantity -+ Add to Cart Add to Cart Custom Options Price as Configured Add to Cart View Cart Articles & Videos About This Item ALL ARTICLES ALL VIDEOS Overview / Product DescriptionSea & Sea NX Extension Ring 40L with Port Lock[ Specifications ][Dimensions (DIAxD)] 129 x 55.5mm / 5.1 x 2.2 inches[Weight] Approx. 234g / 8.3 oz[Depth rating] 100m / 330ft[Construction] Corrosion-resistant aluminum alloy (alumite coating)[Distance] Between the mount and the front end: 40mm / 1.6 inches (with port lock)