The model 3656 offers close coupled design for space saving and simplified maintenance;The model 3756 offers a bearing frame mounted design for flexibility of installation and drive arrangements;Back pull-out to reduce maintenance down time;Standard Type 21 mechanical seal for both reliability and availability. Carbon/ceramic/ BUNA standard, with other faces and elastomers available;3656/3756 available in all iron, bronze fitted or all bronze construction for application versatility;Replaceable wearing components include stainless steel shaft sleeve and casing and hub wear rings to maintain peak efficiency;Packed box sealing is also available as an option;Enclosed impeller design, dynamic balancing and renewable wear rings reduce losses affecting performance and pump life;Suction and discharge pipe connections are NPT threaded, except 3 x 4 7 which has 125 lb. ANSI flat faced flanges;Rigid cast iron motor adapter provides support and registered fits maintain positive unit alignment;Standard NEMA motor frame, JM or JP shaft extension, C-face mounting, single phase or three phase, 3500 or 1750 RPM. Open drip proof and totally enclosed fan cooled;Optional explosion proof or high efficiency motors available;Optional rigid carbon steel bedplate, sheet metal coupling guard and T. B. Woods spacer coupling for 3756 models