Product Description Packing list: 1 * T8x2 800mm lead screw 1 * T8x2 brass nut The lead of the thread is 2mm, which means that the nut will move 2mm if the nut turns one circle. The advantages of the lead screw are: Large load carrying capability Compact Large mechanical advantage Precise and accurate linear motion Smooth, quiet, and low maintenance, very suitable for 3D printer z axis. Minimal number of parts So this lead screw is very suitable for 3D printer Z axis, such as Ultimaker and Prusa i3. The screw type of this lead screw is ACME thread. ACME Threads are generally stronger than square threads due to their trapezoidal thread profile, which provides greater load-bearing capabilities. #productDescription { color: #333333; word-wrap: break-word; font-size: small; line-height: initial; margin: 0.5em 0px 0em 25px; } #productDescription_feature_div > h2.default { font-size: medium; margin: 0 0 0.25em; } #productDescription_feature_div > h2.books { color:#333 !important; font-size:21px !important; line-height: 1.3; padding-bottom: 4px; font-weight: normal; margin: 0px; } #productDescription_feature_div > h2.softlines { color:#333 !important; font-size:21px !important; line-height: 1.3; padding-bottom: 4px; font-weight: bold; margin: 0px; } #productDescription > p, #productDescription > div, #productDescription > table { margin: 0 0 1em 0; } #productDescription p { margin: 0em 0 1em 1em; } #productDescription h3 { font-weight: normal; color: #333333; font-size: 1.23em; clear: left; margin: 0.75em 0px 0.375em -15px; } #productDescription table { border-collapse: inherit !important; margin-bottom: 0; } #productDescription table img { max-width: inherit !important; } #productDescription table td { font-size: small; vertical-align: inherit !important; } #productDescription ul li { margin: 0 0 0 20px; } #productDescription ul li ul { list-style-type: disc !important; margin-left: 20px !important; } #productDescription ul ul li { list-style-type: disc !important; margin-left: 20px !important; } #productDescription > ul ul li { list-style-type: disc !important; } #productDescription ul li ul li { margin: 0 0 0 20px; } #productDescription .aplus p { margin: 0 0 1em 0; } #productDescription small { font-size: smaller; } #productDescription.prodDescWidth { max-width: 1000px } P.when('jQuery').execute(function($){ $("#productDescription table").each(function() { var width = $(this).attr('width'); if (width) width += 'px'; else width = 'auto'; $(this).css('width', width); var padding = $(this).attr('cellpadding'); if (padding) padding += 'px'; else padding = '0px'; $(this).css('padding', padding); }); }); #productDescription h3 { margin: 0.75em 0px 0.375em -1px; }