This is a cow bone nut & saddle set for ukulele. If you are currently using plastic nuts & saddles, why not try upgrading to a higher quality sound? The grooves are already processed, making installation a bit easier. Size Nut: Approx. 35 x 5 x 7mm Saddle: Approx. 53 x 2.8 x 7mm Caution! Simply attaching new nuts & saddles without any adjustments may not fit your ukulele well. You will need to file them down to achieve a comfortable string height for playing. Generally, you can use sandpaper for this, but please search online for instructions on how to do it. We also have many other guitar maintenance items for sale. Thank you for your interest! (*^^)v We primarily ship via standard mail (no insurance), but postal accidents can occasionally occur. For an additional 60 yen, you can upgrade to Click Post, which includes tracking. Please request this change in the comments. [Notes] - We are closed on Saturdays, Sundays, and public holidays. Shipping will occur on the next business day. - Generally, if payment is received by 3 PM, there is a high chance of same-day shipping. All items are shipped free of charge. - We have stock, so immediate purchase without commenting is welcome. - Items will be shipped in simple packaging. Shipping methods vary by product, so please check. - If you purchase multiple items, there will be a discount equivalent to the shipping cost. Please contact us in the comments before purchasing. - Colors may appear slightly different from the actual product due to lighting conditions and monitor differences. - We strive to answer questions as quickly as possible, but please understand that there may be delays depending on the timing. - For initial defects, we will offer exchanges or refunds, so please contact us before leaving a review. We may not be able to provide support after a review has been left.