Your search for "ex-4pst-rmk" revealed the following:
Juniper EX-4PST-RMK 4-Post Rack Mount Kit for EX Series QFX Series and AFX
SKU: NSH-4937
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
$ 208.99
• Only 2 remaining
Call if you need more
NEW Juniper EX-4PST-RMK EX Series Adjustable 4-Post Rack Mounting Kit
SKU: NSN-6169
Condition: New
Shipping: Overnight Options
Warranty: 365 days
$ 223.99
• Only 2 remaining
Call if you need more
Juniper EX4500-4PST-RMK EX4500 Series 4 Post Rack Mount Kit
SKU: NSH-7427
Condition: Seller refurbished
Shipping: Overnight Options
Warranty: 365 days
$ 244.99
• 25 in stock
Call if you need more