/ip firewall mangle
add action=mark-connection chain=prerouting connection-bytes=\
    262146-4294967295 in-interface=ether1 new-connection-mark=download \
    protocol=tcp src-port=21,80
add action=mark-packet chain=prerouting connection-mark=download \
    in-interface=ether1 new-packet-mark=download passthrough=no

/queue type
add kind=pcq name=shape pcq-classifier=src-address pcq-dst-address6-mask=64 \
    pcq-rate=128k pcq-src-address6-mask=64

/queue tree
add max-limit=128k name=Download packet-mark=download parent=global queue=\
    shape

Not: ether1 = WAN interface

if you have two ISP and configure as load Balancing, you must add two Mangle

Ex.
/ip firewall mangle
add action=mark-connection chain=prerouting connection-bytes=\
    262146-4294967295 in-interface=ether1 new-connection-mark=download \
    protocol=tcp src-port=21,80
add action=mark-packet chain=prerouting connection-mark=download \
    in-interface=ether1 new-packet-mark=download passthrough=no

/ip firewall mangle
add action=mark-connection chain=prerouting connection-bytes=\
    262146-4294967295 in-interface=ether2 new-connection-mark=download \
    protocol=tcp src-port=21,80
add action=mark-packet chain=prerouting connection-mark=download \
    in-interface=ether1 new-packet-mark=download passthrough=no

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