Small hydraulic hose end chamber with a 1/2 in NPT nipple, which you can connect to your hydraulic coupler, not included. Has a 5.41 cu in chamber capacity, and a drain plug. This size is suitable for most single hydraulic cylinder attachments or implements, as well as case drain line couplers on hi-flow attachments or implements. To be used on hydraulic hoses while not in use to prevent pressure build up from thermal expansion. Drain plug can be used to periodically drain any residual oil in the hose end chamber to prevent build up. Handle/Hook is used to hang the hose end chamber vertically while hooked to implement. Made in USA.