This listing is for FOUR (4) padlocks keyed alike (same key unlocks all four) and eight keys. These padlocks are ideal for all outdoor applications when needing multiple locks that utilize ONLY one key. To fit coupler latch: remove the shackle sleeve. Shackle fits standard opening of 9/32′ (7mm). Note that non-rigid shackle has enough play to fit virtually all coupler latches less than 7/8′ wide. IMPORTANT NOTE – If using this style lock on a trailers coupler latch please be aware it is NOT recommended for all 2-5/16 couplers. It will fit some 2-5/16 couplers, the exception being 2-5/16 couplers that have the latch partially recessed from the top surface of the coupler, or latches that are wider than 7/8. The #37 latch lock works well on 1-7/8 and 2 inch couplers and on virtually all standard hasp applications. You can order up to eight locks keyed alike. For quantities greater than eight please inquire and we can normally have them in a couple of days. This style lock is also available in a 2-pack and a 3-pack. To purchase visit our Amazon Store (click on our logo), or via the Master Lock link under this pages title. To reach any desired quantity order a combination of 2-packs, 3-packs, 4-packs.