Thanks Arthur, I got them

Arthur this is what I require, 2X8gb

Thanks Len

iMac (Retina 5K, 27-inch, 2017)

Get memory specifications for iMac (Retina 5K, 27-inch, 2017), then learn how to install memory in this model.

Memory specifications

This iMac model features Synchronous Dynamic Random-Access Memory (SDRAM) slots on the rear of the computer near the vents with these memory specifications:

Number of memory slots4Base memory8GB (2 x 4GB DIMMs)Maximum memory64GB (4 x 16GB DIMMs)

Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria:

PC4-2400 (19200)

Unbuffered

Nonparity

260-pin

2400MHz DDR4 SDRAM

Arthur Shi- my ram is a 260 pin, not 204pin, it is a 27” iMac 2017 Retina 5k

Arthur I will contact you for purchase etc.

My computer is a iMac 27" 2017 RAM Retina 5k- I want to upgrade my Ram, put 1 -8gig in each free slot, talked with Apple service centre and they want $400.+ for this etc. There must be a comparable Ram on the market I could use that would be compatible to use at normal prices etc. Any recommendations. A computer tech from Apple centre recommended I try you folks.

Thanks Len