[Thông Báo] Thay Đổi Thời Gian Xuất Hóa Đơn VAT từ 12-14/05/2026 do Chuyển Địa Chỉ Kinh Doanh. Xem chi tiết .
[Announcement] VAT Invoice Schedule Adjustment during May 12-14, 2026 due to Office Relocation. See more .
Toothed Washer Nuts/Grooved Hex Nuts Toothed washers have teeth on the inner side, the outer side, or both, so that the teeth bite into the fitting part to prevent loosening. Grooved hex nuts can prevent loosening by inserting a pin to lock the bolt into the hole and castle-like groove.